Slides in this set
19 The Internet
·The Internet links private PCs, public networks and
business networks together using telephone lines to form
one vast world-wide network. It allows computer users to
share and exchange information with each other wherever
they are in the world.
·information on the Internet comes in many different
formats. E.g.simple e-mail text files, music, video clips,
computer software…read more
Connecting to the Internet
·A computer with a modem and access to a telephone line is needed.
·Faster connection is possible with a special type of digital telephone
line called an ISDN line which doesn't need a modem.
·Larger organisations use a leased line
·A leased line is a private telephone line which is permanently open
24 hours a day.
·Very high speed digital lines are available but these cost hundreds of
thousands of pounds per year to use. computers on a local area
network need to be connected to the Internet using an ISDN or
leased line a device called a router
·A router is a special piece of hardware which co-ordinates the
switching of messages between the computers and the rest of the
·Find an Internet Service Provider (ISP)…read more
The World Wide Web (WWW)
·World Wide Web is largest part of the Internet
·Pages of information begin at `home page'
·Pages are linked together using hypertext
·Hypertext generated using Hypertext Mark-up language or HTML…read more
·Uniform Resource Locator
·These give the location of individual sites on the World
·Most start with http//:www.
·They often reveal the country of origin such as .uk for
the United Kingdom. They also indicate whether the site is
commercial with either .co or .com, a government
organisation with .gov, or an academic organisation with
·Allow Internet users to buy goods or services online any time day or night
without needing to travel anywhere or get pushed around in crowded shops
·Some companies do all of their business over the Internet…read more