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1.1 What is Internet
The Internet is a network of millions of computers
connected together in some way so that they could share information. . A network
could be as simple as two computers connected to each other or it could be as
complex as millions of computers connected to each other like the Internet. In
order for a computer to be part of a network it has to be connected to another
computer that is also part of that network .This allows computers to "talk" to
each other using certain protocol. They could share files and other information.
This is the way our email, the World Wide Web and other services work over the
Internet.
Each computer on the
Internet has an address. This address is also called an Internet Protocol
address(IP address). An IP address contains two important pieces of information:
Where the computer is located and what kind of network it is on. When a computer
wants to send information to another computer it puts a label on the message
which contains the IP address of the computer for which the information is
intended. The information then pass through a chain of computers on the
Internet. When a computer receives a packet of information it looks at the label
and sends it in the direction of where the IP address is located. The
information eventually makes its way to the computer with the correct IP
address. It does not really matter how far apart two computers are. As long as
they are both connected to the same network, they could share information.
Servers are machines that
make information available to other people on the Internet. They are primarily
powerful computers that store information like email, web pages and databases.
They are usually on 24 hours a day so that we could access the information any
time anywhere. In order for a web page to be visible to others on the Internet,
it must be put on a server.
There are a number of services on
the Internet that enable computers to share and access information. Among them,
the most popular one is the World Wide Web. The reason why it has become so
popular so fast is because it provides multimedia information and interaction.
Images, text, animation, movies, games and many other information could be
shared between computers. Each web page has its own Internet address called
URL(Uniform Resource Locator) so that Internet users could access it using
standard browser such as Mozilla Firefox, Internet Explorer and Safari. In
the past, Web pages were basically
designed using HTML code. An the most popular HTML editor is notepad. Nowadays
most web pages are designed using GUI-based website building programs such as
Microsoft Frontpage and Macromedia Dreamweaver. However, sound knowledge of HTML
is still very important especially when to need to troubleshoot and customize
your website. |