A dial-up Internet connection is becoming more rare due to broadband and wireless Internet connections, but is still fairly common. A dial-up connection means that you use your telephone line to connect to an outside Internet Service Provider (ISP), which in turn connects you to the Internet. The parts of a dial-up connection include a modem, which transmits the signal from your computer to your phone line, and connects it to the modem at your ISP, as well as a telephone line.
How It Connects to the Internet
In order to connect to the Internet, the user first has to give the signal on the computer for it to connect. For instance, you usually double-click on the server icon (e.g., Internet Explorer or Mozilla), which initiates the dial-up process. You will hear a phone number being dialed, and then a series of clicks and beeps as the connection is being modulated to connect to your ISP's modem. Once it is done, it has acquired an Internet Protocol (IP) address from the ISP, which enables your computer to connect to the Internet network.
Pros and Cons
Dial-up connections are the most inexpensive type of Internet connection you can purchase, but this comes at a heavy price. Most of all, dial-up connections can be slow, both in connecting to the Internet and in loading Internet websites. This is because the phone line used in dial-up connects permits only a fairly limited stream of data from the ISP. For example, most dial-up connections allow about 56 kilobits per second while broadband permits as much as 512 kilobits per second, which makes a world of difference in terms of the speed of your Internet connection.