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 Netscape Navigator and Internet Explorer.
Web pages are designed using HTML. |