Modems made simple

Chad Underwood
3 min readMar 1, 2022
Photo by Stephen Phillips - on Unsplash

From the 1980’s through the late 1990’s, the dial up modem (modulator-demodulator) was used most.

Dial up internet wasn’t available for the general population until 1992. Once it was available the dial-up modem was the way to get connected to the internet.

What does a dial-up modem do?

The dial-up modem takes a digital signal from a computer. Then turns the digital signal into an analog audio signal. This conversion makes the telephone system able to use the signal.

How does a dial-up modem work?

The dial-up modem is plugged into an telephone jack (outlet) in the wall. Then plugged into your computer. With dial-up internet your data is sent through a dial-up modem through a telephone line.

It’s speeds were slow. The max speeds of the fastest dial-up modem was 56kbps (kilo bits per second) 56,000 bits or 7kB kilobytes. For perspective, this is the size of a really small text file (not a word document but a notepad .txt file). But you would never get these speeds in real life.

This is why text based apps like IRC and simple mainly text websites were the norm. Text is low data so the refreshes happened fast.

Are Modems used today?

Modems are still used today. But you probably call it a router. You probably rent your modem from your ISP.

  • DSL (digital subscriber lines) modems are connected to telephone wall jack (place to connect a cable into the wall).
  • Cable based internet is connected to a coax jack in the wall.
  • Fiber modems are connected to a fiber line run into your house by the phone company.
  • Dial-up with the invention of mobile hotspots (internet connection using your mobile phone as a modem) their use has declined. But there are still some areas where this is the only option.

The speeds of current modems are way faster. The slowest I have seen lately, in the US, is 100Mbps (megabits per second). This is equal to 12,500 kilobytes. The faster speeds allow the cloud and web apps to exist.

What do current modems do?

Chad Underwood

American writer sharing experiences in life, writing, technology, and content creation.