A modem converts data into a signal so that it can be easily sent and received over a telephone line, cable, or satellite connection. For transmission over an analog telephone line, once the most popular way to access the Internet, the modem converts data between analog and digital formats in real time for two-way network communication. In the case of the high-speed digital modems that are popular today, the signal is much simpler and the analog-to-digital conversion is not necessary.
Modem vs. Router – What’s the Difference?
The first devices, called modems, converted digital data for transmission over analog telephone lines. The speed of these modems was measured in baud (a unit of measurement named after Emile Baudot), although these measurements were converted to bits per second as computer technology developed. The first commercial modems supported a speed of 110 bps and were used by the U.S. Department of Defense, news agencies, and some large corporations.
Modems gradually became popular with consumers in the late 1970s through the 1980s when public message boards and news services such as CompuServe were built on early Internet infrastructure. Then, with the explosion of the World Wide Web in the mid- to late 1990s, dial-up modems emerged as the primary form of Internet access in many homes around the world.
Modems used on dial-up networks convert data between the analog form used on telephone lines and the digital form used on computers. An external dial-up modem is connected to a computer on one end and to a telephone line on the other. In the past, some computer manufacturers integrated internal dial-up modems into the computer.
