1. How
did the Internet Evolve ?
The Advanced Research Projects Agency Network
(ARPANET) developed by ARPA of the U.S. Department of Defense was the world's
first operational packet switching network, and the progenitor of the global
Internet. During the 1950s, several communications researchers realized that
there was a need to allow general communication between users of various
computers and communications networks. This led to research into decentralized
networks, queuing theory, and packet switching. The subsequent creation of
ARPANET in the United States in turn catalyzed a wave of technical developments
that made it the basis for the development of the Internet. The first TCP/IP
wide area network was operational in 1984 when the United States' National Science
Foundation (NSF) constructed a university network backbone that would later
become the NSFNet. It was then followed by the opening of the network to
commercial interests in 1995. Important separate networks that have
successfully entered the Internet include Usenet, Bitnet and the various
commercial and educational X.25 networks such as Compuserve and JANET. The
collective network gained a public face in the 1990s. In August 1991 CERN in
Switzerland publicized the new World Wide Web project, two years after Tim
Berners-Lee had begun creating HTML, HTTP and the first few web pages at CERN
in Switzerland. In 1993 the Mosaic web browser version 1.0 was released, and by
late 1994 there was growing public interest in the previously
academic/technical Internet. By 1996 the word "Internet" was common
public currency, but it referred almost entirely to the World Wide Web.
Meanwhile, over the course of the decade, the Internet successfully
accommodated the majority of previously existing public computer networks
(although some networks such as FidoNet have remained separate). This growth is
often attributed to the lack of central administration, which allows organic
growth of the network, as well as the non-proprietary nature of the Internet
protocols, which encourages vendor interoperability and prevents any one
company from exerting too much control over the network. The IEEE has assigned
the 802.1 label to the internetworking among 802 LANs, MANs and other wide area
networks, now known as the Internet.
2. What are the various types of internet
connections, and what are the differences between broadband and dial-up
connection ?
Analog: Dial-up Internet Access
Also called dial-up access,
an analog Internet connection is both economical and slow. Using a modem connected to
your PC, users connect to the Internet when the computer dials a phone number
(which is provided by your ISP) and connects to the network. Dial-up is an
analog connection because data is sent over an analog, public-switched telephone network.
The modem converts received analog data to digital and vice versa. Because dial-up
access uses normal telephone lines the quality of the connection is not always
good and data rates are limited. Typical Dial-up connection speeds range from
2400 bps to 56 Kbps. Today, analog has been widely replaced by broadband (Cable
and DSL).
ISDN - Integrated Services Digital Network
Integrated services digital network
(ISDN) is an international
communications standard for sending voice, video, and data over digital
telephone lines or normal telephone wires. Typical ISDN speeds range from 64
Kbps to 128 Kbps.
B-ISDN - Broadband ISDN
Broadband ISDN is
similar in function to ISDN but it transfers data over fiber optic telephone
lines, not normal telephone wires. SONET is the physical transport backbone of
B-ISDN. Broadband ISDN has not been widely implemented.
DSL – Digital Subscriber Line
DSL is frequently referred to as an
"always on" connection because it uses existing 2-wire copper
telephone line connected to the premise so service is delivered simultaneously
with wired telephone service -- it will not tie up your phone line as an
analog dial-up connection does. The two main categories of DSL for home
subscribers are called ADSL and SDSL. All types of DSL technologies are
collectively referred to as xDSL. xDSL
connection speeds range from 128 Kbps to 9 Mbps.
ADSL - Asymmetric Digital Subscriber Line
ADSL is
the most commonly deployed types of DSL in North America. Short for asymmetric
digital subscriber line ADSL supports data rates of from 1.5 to 9 Mbps when
receiving data (known as the downstream rate) and from 16 to 640 Kbps when
sending data (known as the upstream rate). ADSL requires a special ADSL modem.
ADSL+2 - ADSL Extension
An extension to ADSL broadband
technology that provides subscribers with significantly faster download speeds
when compared to traditional ADSL connections. ADSL+2 works in the
same fashion as ADSL a special filter is installed on a subscriber's telephone
line to split existing copper telephone lines (POTS) between regular telephone
(voice) and ADSL+2. ADSL2+ service is most commonly offered in highly-populated
metropolitan areas and subscribers must be in close geographical locations to
the provider's central office to receive ADSL2+ service.
SDSL -
Symmetric Digital Subscriber Line
Short for symmetric digital
subscriber line, SDSL is a
technology that allows more data to be sent over existing copper telephone
lines (POTS). SDSL supports data rates up to 3 Mbps. SDSL works by sending
digital pulses in the high-frequency area of telephone wires and cannot operate
simultaneously with voice connections over the same wires. SDSL requires a
special SDSL modem. SDSL is called symmetric because it supports the same data
rates for upstream and downstream traffic.
VDSL - Very High DSL
Very High DSL (VDSL) is a DSL technology
that offers fast data rates over relatively short distances — the shorter the
distance, the faster the connection rate.
Cable - Broadband Internet Connection
Through the use of a cable modem you
can have a broadband Internet connection that is designed to operate over cable
TV lines. Cable Internet works by using TV channel space for data transmission,
with certain channels used for downstream transmission, and other channels for
upstream transmission. Because the coaxial cable used
by cable TV provides much greater bandwidth than telephone lines, a cable modem
can be used to achieve extremely fast access. Cable providers typically
implement a cap to limit capacity and accommodate more customers. Cable speeds
range from 512 Kbps to 20 Mbps.
Wireless Internet Connections
Wireless Internet,
or wireless broadband is one of the newest Internet connection types. Instead
of using telephone or cable networks for your Internet connection, you use
radio frequency bands. Wireless Internet provides an always-on connection which
can be accessed from anywhere — as long as you geographically within a network
coverage area. Wireless access is still considered to be relatively new, and it
may be difficult to find a wireless service provider in some areas. It is
typically more expensive and mainly available in metropolitan areas.
T-1 Lines – Leased Line
T-1 lines are
a popular leased line option for businesses connecting to the Internet and for
Internet Service Providers (ISPs) connecting to the Internet backbone. It is a
dedicated phone connection supporting data rates of 1.544Mbps. A T-1 line
actually consists of 24 individual channels, each of which supports 64Kbits per
second. Each 64Kbit/second channel can be configured to carry voice or data
traffic. Most telephone companies allow you to buy just one or some of these
individual channels. This is known as fractional T-1access. T-1 Lines support
speeds of 1.544 Mbps. Fractional T-1 speeds are 64 Kbps per channel (up to
1.544 Mbps), depending on number of leased channels.
Bonded T-1
A bonded T-1is two or more
T-1 lines that have been joined (bonded) together to increase bandwidth. Where
a single T-1 provides approximately 1.5Mbps, two bonded T1s provide 3Mbps or 46
channels for voice or data. Two bonded T-1s allow you to use the full bandwidth
of 3Mbps where two individual T-1s can still only use a maximum of 1.5Mbps at
one time. To be bonded the T-1 must run into the same router at the end,
meaning they must run to the same ISP. Typical Bonded T-1 (two bonded T-1
lines) speed is around 3 Mbps.
T-3 Lines – Dedicated Leased Line
T-3 lines
are dedicated phone connections supporting data rates of about 43 to 45 Mbps.
It too is a popular leased line option. A T-3 line actually consists of 672
individual channels, each of which supports 64 Kbps. T-3 lines are used mainly
by Internet Service Providers (ISPs) connecting to the Internet backbone and
for the backbone itself. Typical T-3 supports speeds ranging from 43 to 45
Mbps.
OC3 - Optical Carrier
Short for Optical Carrier, level 3
it is used to specify the speed of fiber optic networks conforming to the SONET
standard. OC3 is typically used as a fiber optic backbone for large networks
with large voice, data, video, and traffic needs. Speeds are 155.52 Mbps, or
roughly the speed of 100 T1 lines.
Internet over Satellite
Internet over Satellite(IoS)
allows a user to access the Internet via a satellite that orbits the earth. A
satellite is placed at a static point above the earth's surface, in a fixed
position. Because of the enormous distances signals must travel from the earth
up to the satellite and back again, IoS is slightly slower than high-speed
terrestrial connections over copper or fiber optic cables. Typical Internet
over satellite connection speeds (standard IP services) average around 492 up
to 512 Kbps.
The fundamental difference between dialup and broadband
Internet connections is the manner in which the connection is made from your PC
to the Internet. A dialup service connects to the Internet through your phone
line. The modem in your PC "calls" an Internet Service Provider (ISP)
and connects with a maximum speed of 56,000 bytes per second, better known as a
56K speed connection. Each time your PC dials into the ISP, it is assigned an
Internet Protocol (IP) address, which you can think of as an "Internet
address." A different, unique IP address is assigned at the beginning of
each visit so that the ISP can recognize your PC and make sure you can send and
receive email, surf the Internet, and so on; basically, this address lets your
ISP know where to send the information you are requesting through your modem.
In terms of hackers, in order for someone to gain access to your computer, it
would be necessary for them to know your IP to successfully do so. The fact
that your IP address constantly changes essentially makes your Internet
connection more secure.
In contrast, when you connect to the Internet via a broadband Internet connection, the process is slightly different. Once your PC is connected to the ISP through a cable or DSL connection, it remains connected until the cable box or DSL line is disconnected or physically unplugged. A DSL connection runs through unused wires in your existing phone line without disruption and can translate data at 5 million bytes per second, or 5Mbps. Broadband services are often referred to as "always on" services because it is not necessary to make a setup call to your ISP each time you wish to access the Internet; this means that once you are assigned an IP address, you keep it until you request it to be changed. We'll learn how to do this in a later newsletter.
Connection speed and price are two important considerations when choosing between dialup and broadband. Dialup connection speeds make it more difficult to view certain types of media, such as video, and it can take much longer to download and open email attachments, play online games, and so on. Although the slower connection speed is a disadvantage for dialup users, there are also a few advantages to using this type of connection, which include lower monthly charges and a higher level of security. The cost difference is obvious when comparing the $20-30 per month subscription fee for dialup and the $50-60 per month subscription fee for most broadband services. In terms of security, because the connection is not "always on" and because you are assigned a different IP address each time, it is slightly more difficult to be attacked over the Internet, although nothing is ever fool proof and risks still do exist.
The advantages of a broadband connection can sometimes outweigh some of the disadvantages. The increased connection speed allows for ease in initial connection, duration of connection, no additional phone charges that may apply in dialing into an ISP, and variability of Internet use, such as an increase in allowable file viewing size. However, if you do choose a broadband connection, you'll need to purchase a firewall-which we'll learn more about later-to keep your computer "invisible" to the outside world.
In the ongoing debate of which is better dialup or broadband, there isn't really a clearly correct answer. This question can only be answered by looking at your needs and resources and comparing them to what each option has to offer. If you use the Internet to check email, stock quotes, and visit the occasional website, dialup will be sufficient. But if you frequently download large media files, play games over the Internet, and view sites that are high in image content then you may be more satisfied with broadband service.
In contrast, when you connect to the Internet via a broadband Internet connection, the process is slightly different. Once your PC is connected to the ISP through a cable or DSL connection, it remains connected until the cable box or DSL line is disconnected or physically unplugged. A DSL connection runs through unused wires in your existing phone line without disruption and can translate data at 5 million bytes per second, or 5Mbps. Broadband services are often referred to as "always on" services because it is not necessary to make a setup call to your ISP each time you wish to access the Internet; this means that once you are assigned an IP address, you keep it until you request it to be changed. We'll learn how to do this in a later newsletter.
Connection speed and price are two important considerations when choosing between dialup and broadband. Dialup connection speeds make it more difficult to view certain types of media, such as video, and it can take much longer to download and open email attachments, play online games, and so on. Although the slower connection speed is a disadvantage for dialup users, there are also a few advantages to using this type of connection, which include lower monthly charges and a higher level of security. The cost difference is obvious when comparing the $20-30 per month subscription fee for dialup and the $50-60 per month subscription fee for most broadband services. In terms of security, because the connection is not "always on" and because you are assigned a different IP address each time, it is slightly more difficult to be attacked over the Internet, although nothing is ever fool proof and risks still do exist.
The advantages of a broadband connection can sometimes outweigh some of the disadvantages. The increased connection speed allows for ease in initial connection, duration of connection, no additional phone charges that may apply in dialing into an ISP, and variability of Internet use, such as an increase in allowable file viewing size. However, if you do choose a broadband connection, you'll need to purchase a firewall-which we'll learn more about later-to keep your computer "invisible" to the outside world.
In the ongoing debate of which is better dialup or broadband, there isn't really a clearly correct answer. This question can only be answered by looking at your needs and resources and comparing them to what each option has to offer. If you use the Internet to check email, stock quotes, and visit the occasional website, dialup will be sufficient. But if you frequently download large media files, play games over the Internet, and view sites that are high in image content then you may be more satisfied with broadband service.
3. What
are the types of internet provider ?
Access providers
Access
ISPs employ a range of technologies to enable consumers to connect to their
network. Over time, available technologies have ranged fromacoustic couplers to telephone lines, to cable, wi-fi,
and fiber optics.
For users and small
businesses, traditional options include copper wires to provide dial-up, DSL (typically asymmetric digital subscriber line,
ADSL),cable
modem or Integrated Services Digital Network (ISDN) (typically basic rate interface). Using fiber-optics to end users is
called Fiber
To The Homeor similar names.
For customers with
more demanding requirements, such as medium-to-large businesses, or other ISPs,
higher-speed DSL (such as single-pair high-speed
digital subscriber line ), Ethernet, metropolitan
Ethernet, gigabit
Ethernet, Frame Relay,
ISDN Primary Rate Interface, ATM (Asynchronous Transfer Mode) and synchronous optical networking (SONET) can be used.
Mailbox providers
A mailbox provider is a department or
organization that provides email mailbox hosting services. It provides email servers to send, receive,
accept, and store email for other organizations and/orend users, on their behalf and upon
their explicit mandate.
Many mailbox
providers are also access providers, while others aren't
(e.g., Yahoo! Mail, Hotmail, Gmail, AOL Mail, Pobox). The definition given in RFC 6650 covers email hosting services, as well as the
relevant department of companies, universities, organizations, groups, and
individuals that manage their mail servers themselves. The task is typically
accomplished by implementingSimple Mail Transfer Protocol (SMTP) and possibly
providing access to messages through Internet Message Access Protocol (IMAP), the Post Office Protocol, Webmail, or a
proprietary protocol.
Hosting ISPs
Hosting ISPs routinely provide
email, FTP, and web-hosting services. Other
services include virtual machines, clouds, or entire physical servers where
customers can run their own custom software.[citation needed]
Transit ISPs
Just as their
customers pay them for Internet access, ISPs themselves pay upstream ISPs for
Internet access. An upstream ISP usually has a larger network than the
contracting ISP and/or is able to provide the contracting ISP with access to
parts of the Internet the contracting ISP by itself has no access to.
In the simplest case,
a single connection is established to an upstream ISP and is used to transmit
data to or from areas of the Internet beyond the home network; this mode of
interconnection is often cascaded multiple times until reaching a Tier
1 carrier. In reality, the situation is often more complex. ISPs with more
than one point
of presence (PoP) may have
separate connections to an upstream ISP at multiple PoPs, or they may be
customers of multiple upstream ISPs and may have connections to each one of
them at one or more point of presence. Transit ISPs provide large amounts of bandwidth for connecting
hosting ISPs and access ISPs.
Virtual ISPs
A virtual ISP (VISP) is an
operation which purchases services from another ISP (sometimes called a
"wholesale ISP" in this context)[14] which allow the
VISP's customers to access the Internet using services and infrastructure owned
and operated by the wholesale ISP. It is akin to mobile virtual network operators and competitive local exchange carriers for voice
communications.
Free ISPs
Free ISPs are
Internet service providers which provide service free of charge. Many free ISPs
display advertisements while the user is connected; like commercial television,
in a sense they are selling the users' attention to the advertiser. Other free
ISPs, often called freenets, are
run on a nonprofit basis, usually with volunteer staff.
Peering
ISPs may engage in peering, where
multiple ISPs interconnect at peering
points or Internet exchange points (IXs), allowing
routing of data between each network, without charging one another for the data
transmitted—data that would otherwise have passed through a third upstream ISP,
incurring charges from the upstream ISP.
ISPs requiring no upstream
and having only customers (end customers and/or peer ISPs) are called Tier
1 ISPs.
Network hardware,
software and specifications, as well as the expertise of network management
personnel are important in ensuring that data follows the most efficient route,
and upstream connections work reliably. A tradeoff between cost and efficiency
is possible.
4. What is the
purpose of an IP address and what is its relationship to a domain name ?
An IP Address is classified as an address
primarily because it serves the same purpose as a home address or an office
address- it allows each machine present on the Internet to be located. Websites
are able to track visitors' locations and determine the pages that they are
interested in through their IP Address. It can also be used to identify a
specific user if there is a request for log records through the user's Internet
Service Provider or ISP. Unlawful behavior on the Internet can call for investigation,
and law enforcement has the discretion to subpoena the ISP so that the name and
contact details of the owner of a certain IP Address can be obtained.
The Internet was
formally formed in a small number of computers, it linked to modems and telephone
lines. From that, you need to provide the IP address to connect with modems and
telephone lines.
Not long after that a problem arises when more and more hosts created, the current system cannot afford to maintain the raising data. Due to the limitation the domain name was introduced. The domain name means to simplicity the process, so the Network Information Center once again regaining its ability to maintain the internet. But again it become tough when the text file multiply, the current solution need to fine tune again. Responding to the problem University of Wisconsin in 1983 invented the very first Domain Name System, it converts the texts names into IP address in more convenient way.
The system works very well and people started to follow them, the system has been used since then until now. The creation of IP address lessens the trouble and difficulties in connection between people and computers. This is how the World Wide Web (WWW) becomes global easily instantly. That is the feedback from user around the world, never the less find out more about it.
The IP address and domain name are two different identities, but their roles are same to the world. They are connected and supporting each other, the IP address needs the domain name to function properly. So does to domain name, it cannot go online without connecting to IP address.
Now you have the picture about it, let's go to further explanation. IP address formed in 30-bit numeric address, it consists of four group of number divided by dots. Here is an example x.xxx.xx.xxx/1.160.10.240 (four different group numbers). Every group number represent network, there is no fixed format on IP address but each of them are unique and different. The Ip address can work in either sides, it can be a network for domain name or a host for networks.
I believe that you get the real picture by now. The domain name represents single or several IP address. Now we know that IP address and domain name are bound to each other, web pages will lose the identity without them. For an instance if you look for certain site page, you usually will type the domain name to get there. What happen exactly here is the domain name converts to IP address and directly to the site.
That's how they work in a system, once again you can use the domain name or IP address to locate site page easily now.
5.
What is the purpose
of web browser and what are the components of a web address ?
The purpose
of a web browser is to visually bring information to the user. It also visually
displays images, videos and texts that are stored in the computer or websites
in an organised way. The history of web browsers dates back to the 80s after
which numerous improvements and inventions have made it what it is today.
Protocol
The address starts with the communication
protocol, essentially the language in which the computers communicate. Examples
of protocols include “http://” (hypertext transfer protocol), “ftp://” (file
transfer protocol), “pop” (post office protocol). These are the three protocols
you'll come across most often in your business, with http used for your site,
ftp to transfer files to your server and pop for your email.
Domain Name
To the right of the protocol are the
subdomains and the main domain name. http://www.subdomain.first-level-domain.com
Domain names are an important factor in search engine optimization (SEO). So,
if your domain name is “tucsonhardwarestore.com,” your site is more likely to
appear in a search for “Tucson hardware store." Domains with hyphens
should be avoided as they are less well-suited to SEO than non-hyphenated
domains. Note that Google treats subdomains as separate sites when ordering
search results – that is, any authority garnered by the first-level domain will
not pass to the subdomain. So in most cases it is better to use folders to
separate different parts of the site.
Top-Level Domains
The next part of the domain is the
top-level domain, or TLD. These are used to help browsers find your site on the
Internet. Examples include “.com,” “.org”, “.net” and “.edu.” Generally
speaking, it's better to get a .com domain, as this is where people will tend
to look for you. If the .com you want is taken, Gigaom recommend you try a
slight variation such as adding your city name into the URL, before you settle
for a different TLD.
Files and Folders
The rest of the domain works in a
similar way as the folders on your hard drive, so in this address:
http://www.subdomain.first-level-domain.com/articles/article1.html “articles”
is a folder on the server and “article1.html” is a file inside that folder. As
with the domain names, it's important to keep your files and folders
human-friendly. For example, a file name “important-factors-in-buying-a-shed”
is preferable to “contentID=1228” – people will be able to see instantly
whether the content is relevant to them, and the keywords will also help you
rank higher in search engine results.
6.
How do you use
search engine to search for information on the web and what is the difference
between search engine and subject directory ?
Search engines on the World Wide Web are
remotely accessible programs that let you do keyword searches for information
on the Internet. There are several types of search engines and searches may
cover titles of documents, URL's, headers, or full text. Keep in mind that the
results you get from one search engine may not match the results you get from
another search engine. In fact, they are often different due to the way each
search engine behaves. Therefore, it may actually be beneficial to use more
than one search engine on a regular basis.
Google
When you first go to the Google Web site there
is a blinking cursor in an edit box where you can type the word or phrase that
you are interested in.
Google Instant is a search enhancement that
shows results as you type. It is designed to predict a person's search by
updating the page and showing results while you type. It is a time-saving
feature. However, because the page is changing as you type this can sometimes
cause problems for screen reader users. You may find a link on the page that
reads "Screen reader users, click here to turn off Google Instant."
If you choose this link it makes your searches using a screen reader much
easier.
To change your
preferences for Google you can do the following:
1. Press INSERT+F7 to open the JAWS list of links.
2. Choose
the link Options, and then
press ENTER. A links submenu
opens on the Google site.
3. Press DOWN
ARROW to move to
the link Search Settings, and
then press ENTER.
4. Beneath
the heading Google Instant predictions is an On/Off slider bar. At the time of
this writing it does not read well with JAWS. Press ENTER on it to go into forms mode.
5. Press DOWN
ARROW on this
slider bar to turn the feature off.
6. Press NUM
PAD PLUS to get
out of forms mode.
7. Press B to move to the Save button at the
bottom of the page, and then activate it by pressing ENTER.
To begin searching, for users of JAWS prior
to version 10.0, the first thing you need to do is press the ENTER key to go into Forms Mode with JAWS. Once
you are in Forms Mode, you can then type in keywords that will define your
search.
If you are using JAWS 10.0 or later, forms
mode comes on automatically when you get to a Web page which has the focus set
to a blinking cursor in an edit box. If for some reason forms mode does not
come on automatically on your computer, you can also press ENTER to go into forms mode, or you can
pressINSERT+F5 to open the Select a Form Field dialog
box for JAWS.
After you have
typed in some text, press ENTER to activate the Search button.
Google only returns Web pages that contain
all of the words in your query. If you find that you get too many
"hits" or Web pages that match your search, you can enter more words
in your search query to narrow the choices.
Using good keywords gives you better results.
Be as specific as you can. For example, a search for the keyword
"musicians" will yield far more results than a search for the
keywords "Elvis Presley." You do not need to include "and"
between terms, but the order in which you type your keywords will affect the
search results. You can also search for a specific phrase by including words in
quotation marks. Google searches are not case sensitive.
You can also use
the following items within your keywords for Google searches:
·
- (minus) sign. Causes Google to
exclude a word from your search. For example, "JAWS" can refer to a
screen reading software or a famous movie. You can exclude many of the
movie-related hits by searching for "JAWS -movie." (Be sure to include
a space before the minus sign and no spaces between the minus sign and the word
"movie.") Searches for JAWS with different conditions yielded the
following results:
o JAWS,
about 50,600,000 hits
o JAWS
windows -movie, about 8,600,000 hits
o "JAWS
screen reader" (in quotes) about 62,000
As you narrow your
search and use better keywords, you get more relevant results.
·
Putting a phrase into quotes tells
Google to look for the exact words in that exact order.
·
You can search for something within a
specific website by typing the word or phrase followed by site:FreedomScientific.com (where the dot com changes to whatever
site you are searching.
The I'm Feeling Lucky™ button takes you directly to the first
Web page Google returned for your query. You will not see the other search
results at all. For example, to find the home page for Stanford University,
simply enter "Stanford" into the search box and choose the I'm
Feeling Lucky™ button.
Google takes you directly to www.stanford.edu, the official home page of
Stanford University.
Try typing different things such as names,
phone numbers, and more to find people or things.
Try a search for Freedom Scientific. Use this link to go to the Google Web site. On the results
page, there are a couple of things you can do to get more information about the
results of the search:
·
The statistics of your search are
typically placed between the search edit box and the search results. You can
press DOWN ARROW a few times to find this line, or you
can use the JAWS find command CTRL+F to look for the word
"Results," and then read that line. For example, when testing this,
the search found, "About 86,400,000 for freedom scientific. (0.22
seconds)." This can be useful if you need to narrow the search.
·
Google uses a "main" ARIA landmark to guide you
to the search results. You
can press SEMICOLON to move from one ARIA landmark to
another.
·
The items found as a result of your
search are placed on the page as both links and headings. You can press the
navigation quick key H to move quickly among the headings
that match your search. Since they are also links, you can press ENTER to activate them and move to those Web
pages of interest.
·
Below each heading (and link) that
match your search is a short synopsis of what that page is about. After
pressing H to move to a heading (link), just
press DOWN ARROW to read the text below it for more
information.
·
Remember, you can also press SHIFT+H to move backwards.
·
There is also a good structure to the
headings. The heading level one on the page is the Google logo and link that
will take you back to the main Google page. The search results begin to be
listed after a heading level two. The matches found for the search are all
level three headings.
You can also read through the search results
page using normal reading keys or use INSERT+F7 to open the list of links and see what
related links were found. Use the Move to Link button in the links list ALT+M)
to move to a particular link and then down arrow through the associated text to
find out if this might be what you are looking for.
In addition to the information displayed on
the initial results page, there are often links to more pages of information
that meet your search criteria. These pages are reached by activating the link
for the number of the page. Usually you will find links for additional pages 2
through 10 near the bottom of each page. Each page beyond the first page also
contains a number of items that match your search.
Google Search Tools
Google also
provides easy-to-use search tools. For example:
·
"Weather Chicago" yields the
current weather in Chicago
·
"25 kilometers in miles"
converts kilometers to miles
·
"Define screen
magnification" yields definitions for screen magnification
·
"Seafood restaurants 33716"
yields restaurants that serve seafood in or near that zip code
·
And so on...
Yahoo!.com
Yahoo! is another search engine that many
people use. The main Yahoo! page also has more information on it, such as
sports and news headlines, entertainment links, and links to many other items.
This tends to cause the page to appear more cluttered than the Google site, but
may prove itself useful to you as well. As with Google, when you first go to
the Yahoo! Web site there is a blinking cursor in an edit
box.
For users of JAWS prior to version 10.0, the
first thing you need to do is press the ENTER key to go into Forms Mode with JAWS.
Once you are in Forms Mode, you can then type in keywords that will define your
search.
If you are using JAWS 10.0 or later, forms
mode comes on automatically when you get to a Web page which has the focus set
to a blinking cursor in an edit box. If for some reason forms mode does not
come on automatically on your computer, you can also press ENTER to go into forms mode, or you can
pressINSERT+F5 to open the Select a Form Field dialog
box for JAWS.
After you have
typed in some text, press ENTER to activate the Search button.
Yahoo! behaves very much the same way as
Google and displays a list of hits of matching items. These are links to
further resources, and each link here also has a text description taken from
that source that matches your query.
After a Yahoo! results page loads, press the
letter H to move to the different headings on
the page. Below the heading Search Results, you find the main links that match
your search. Each contains a short text synopsis below it and a link for a
cached version. Since the headings are also links, pressing ENTER on one takes you to the Web page
indicated. Beneath each heading/link is text that describes a little bit about
that page. Press INSERT+F7 to use the list of links to explore
the links, or you can also press TAB to move from one link to another.
To find the number of matches, use the JAWS
Find and look for the word "results" without the quotes. You should
hear something like the following: "50,300,911 results."
Yahoo! also has links to other results pages,
just as Google does. These links show as numbers 2 through 10 and are located
near the bottom of the page.
A search engine makes use of robots to index websites; while
a directory uses human editors to list websites. They are two different types
of search services that are often mistakenly confused with one another. Another
difference between a search engine and a directory is that directories use
humans to manually add websites to their database.
7.
What are the types
of web sites ?
Commercial
|
The
purpose of this type of website is to sell products or services. The Internet
address often ends with .com
|
Country
codes
|
Websites
from other countries have a country code at the end. For example Great Britain
is .uk and Canada is .ca
|
Educational
|
The
purpose of this type of website is to provide information about an
educational establishment. The Internet address ends in .edu.
|
Entertainment
|
The
purpose of this type of website is to entertain and provide amusement. The
Internet address often ends with .com
|
Government
|
The
purpose of this type of website is to provide information produced by
government agencies, offices, and departments. Usually, information provided
by government websites is very reliable. The Internet address often ends
with .gov.
|
Military
|
The
purpose of this type of website is to provide information about the military.
The Internet address ends in .mil.
|
News
|
The
purpose of this type of website is to provide information about current
events. The Internet address often ends with .com.
|
Organizational
|
The
purpose of this type of website is to advocate an individual's opinion or a
group's point of view. The Internet address often ends with.org.
|
Personal
|
The
purpose of this type of website is to provide information about an
individual. The Internet address has a variety of endings.
|
8.
How do web pages
use graphics, animation, audio, video, virtual reality, and plug-ins ?
Many exciting Web
pages use multimedia. Multimedia refers to any application that
integrates text with one of the following elements: graphics, sound, video,
virtual reality, or other media elements.
A graphic is a digital
representation of information such as a drawing, chart, or photograph. Two
common file formats for graphical images on the Web are JPEG (Joint Photographic Experts Group) and GIF (Graphics Interchange Format), which
use compression techniques to reduce the size of graphics files and thus speed
downloading.
Animation is the appearance of motion created by displaying a series of
still images in rapid sequence. One popular type of animation, called an animated GIF, uses computer animation and graphics software to
combine several images into a single GIF file.
Audio is music, speech, or any other sound. A common format for audio
files on the Web is MP3, a popular technology that
compresses audio. More advanced Web audio applications usestreaming audio, which transfers audio data in a continuous and even flow,
allowing users to listen to the sound as it downloads. Video consists of
full-motion images that are played back at various speeds. Video files often
are quite large in size. The Moving Pictures Experts Group (MPEG) defines a popular video compression standard. Streaming video allows
you to view longer or live video images as they are downloaded.
Virtual reality (VR) is the use of
computers to simulate a real or imagined environment that appears as a
three-dimensional (3-D) space. A VR world is an entire 3-D site that contains
infinite space and depth.
A
plug-in, or add-on, is a program that extends a browser's capability to
display multimedia elements.
9.
What are the steps
required for web publishing ?
1.
Decide what you want to place on the
web. See the different types of
sites and browse the web for ideas.
o Text
- plain or colored.
o Graphics
§ logos
(e.g. 
)
)
§ ISMAP's
(action dependent on where in the image you select)
o On-line
Forms
§ simple
2.
Decide where on the web, you want
your information placed. Once your information is on the Internet, it is
accessible from everywhere. The availability depends on your web page hoster.
We recommend that you get a domain name so that you are not tied to your web
page hoster.
3.
Convert any documents that you want
placed on the web from their current form to a web readable format. Text should
be in HyperText Markup Language(HTML) format and graphics in GIF(Graphical
Interchange Format)format or JPEG. Some others are possible, but may not be
supported by all web browsers. Any on-line forms will need a program, on the
web server, to process them.
4.
Place your information on-line.
5.
Check to make sure that it looks the
way you want to in several different browsers. Be sure to check both graphical
and textual browsers.
6.
Publish your location to the world.
This gets your information into a wider set of hands than just those who happen
across your location. See Yahoo for
an example. Here are some tips andsubmittal engines.
10.What are the types of E-commerce ?
·
B2B (Business-to-Business)
Companies doing business with each other such as manufacturers selling to distributors and wholesalers selling to retailers. Pricing is based on quantity of order and is often negotiable.
Companies doing business with each other such as manufacturers selling to distributors and wholesalers selling to retailers. Pricing is based on quantity of order and is often negotiable.
·
B2C (Business-to-Consumer)
Businesses selling to the general public typically through catalogs utilizing shopping cart software. By dollar volume, B2B takes the prize, however B2C is really what the average Joe has in mind with regards to ecommerce as a whole.
Having a hard time finding a book? Need to purchase a custom, high-end computer system? How about a first class, all-inclusive trip to a tropical island? With the advent ecommerce, all three things can be purchased literally in minutes without human interaction. Oh how far we've come!
Businesses selling to the general public typically through catalogs utilizing shopping cart software. By dollar volume, B2B takes the prize, however B2C is really what the average Joe has in mind with regards to ecommerce as a whole.
Having a hard time finding a book? Need to purchase a custom, high-end computer system? How about a first class, all-inclusive trip to a tropical island? With the advent ecommerce, all three things can be purchased literally in minutes without human interaction. Oh how far we've come!
·
C2B (Consumer-to-Business)
A consumer posts his project with a set budget online and within hours companies review the consumer's requirements and bid on the project. The consumer reviews the bids and selects the company that will complete the project. Elance empowers consumers around the world by providing the meeting ground and platform for such transactions.
A consumer posts his project with a set budget online and within hours companies review the consumer's requirements and bid on the project. The consumer reviews the bids and selects the company that will complete the project. Elance empowers consumers around the world by providing the meeting ground and platform for such transactions.
·
C2C (Consumer-to-Consumer)
There are many sites offering free classifieds, auctions, and forums where individuals can buy and sell thanks to online payment systems like PayPal where people can send and receive money online with ease. eBay's auction service is a great example of where person-to-person transactions take place everyday since 1995.
There are many sites offering free classifieds, auctions, and forums where individuals can buy and sell thanks to online payment systems like PayPal where people can send and receive money online with ease. eBay's auction service is a great example of where person-to-person transactions take place everyday since 1995.
11.How do I E-Mail, mailing list,
instant messaging, chat rooms, VoIP, newsgroup, and message boards, and FTP
work ?
A variety of services are used widely on the Internet,
including e-mail, FTP, newsgroups and message boards, mailing lists, chat
rooms, and instant messaging. E-mail (electronic mail) is the transmission
of messages and files via a computer network. You use an e-mail program to
create, send, receive, forward, store, print, and delete messages. To receive
messages, you need an e-mail address, which is a combination
of a username and a domain name that identifies a user.
FTP (File Transfer
Protocol) is an Internet standard that allows you to upload and download
files with other computers on the Internet. An FTP server is a computer
that allows you to use FTP to upload files to, and download files from, an FTP site. With anonymous FTP, anyone can transfer
some, if not all, available files. A newsgroup is an online area in which users
conduct written discussions about a particular subject. The computer that
stores and distributes newsgroup messages is called a news server. You use a program called a newsreader to access
a newsgroup, read previously entered messages (called articles), and add (post)
messages of your own.
A thread consists of the original article and
all subsequent related replies. In a moderated newsgroup, a moderator reviews
articles and posts them, if appropriate. A message board is a popular Web-based type of
discussion group that does not require a newsreader and typically is easier to
use than a newsgroup. A mailing list is a group of e-mail names and
addresses given a single name. To add your e-mail name and address to a mailing
list you subscribe to it; to
remove your name, you unsubscribe.
A chat is real-time (meaning
everyone involved in the chat is online at the same time) typed conversation
that takes place on a computer. A location on an Internet server that permits
users to chat is called a chat room. Some chat rooms support voice chats and video chats, where you can hear or see others and they can hear or
see you as you chat. A chat client is a program on your computer that
allows you to connect to a chat server and start a chat session. Instant messaging (IM) is a real-time Internet
communications service that notifies you when one or more people are online and
then allows you to exchange messages or join a private chat room.
12.What are the rules of netiquette ?
Netiquette, which is short for Internet etiquette, is the code of
acceptable behaviors users should follow while on the Internet. Rules for
e-mail, newsgroups, and chat rooms include:
·
Keep messages brief and
use proper grammar and spelling.
·
Be careful when using
sarcasm and humor.
·
Be polite and avoid
offensive language.
·
Avoid sending flames (abusive messages)
and spam (unsolicited
junk mail).
·
Do not use all capital
letters, which is the equivalent of SHOUTING!
·
Use emoticons (such as :) for smile)
to express emotion.
·
Use abbreviations (such
as BTW for by the way) for popular phrases.
·
Clearly identify a spoiler, which is a message that
reveals a solution to a game or an ending to a movie or program.
·
Read the FAQ (frequently asked questions)
document.
·
Do not assume all
material is accurate or up-to-date.
·
Never read someone’s
private e-mail.
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