We can say that the Internet – a global computer network that transfers data between any two computers connected to it. To the network can be connected as a single computer, and a whole local computer network. In the latter case, each computer has a LAN internet access. Internet users connect to the computers of organizations that specialize in providing services to access Internet. Such an organization called the Internet service provider or Internet service providers.
They are often referred to simply as providers. ISPs provide connection of multiple users with different lines. In addition, they are associated with high-speed lines with other providers. The rate of information transfer between providers or between service provider and the individual user may differ by tens of thousands of times. As the communication lines used standard telephone lines, specially laid wire pair or coaxial cable, similar to television, as well as fiber optic cables. In addition, wireless connection, using radio waves.
At the same time can use space satellites, cellular phones, special radios, ground repeaters and other equipment. Depending on the communication channel, Your computer must be equipped with appropriate equipment. Used as a permanent connection and temporary, which is broken at the end of session. Temporary connection is called dial-up. Not all Internet Service Providers are directly connected with each other, but the chain of information could reach any network user. In the design of the Internet, special attention was paid to their reliability. Computers connected to the Internet can be switched at any time, and the network will continue to work.