Once upon a time, people had phones hard-wired in their houses. These phones were called “landlines,” and they relied on wires strung throughout their communities to operate. It was an effective technology, but one that necessarily meant that your ability to place and receive a telephone call was limited to a particular vicinity. Over time, inventors came up with a thing called a “cordless phone,” which extended that range slightly, but not much.
For pollsters, this was useful. There was a phone number that was connected to a house where you knew certain people lived, and so you could call that number and have a good sense that you were talking to Joe Smith, registered Republican.
Then capitalism got in the way. CONT.
Philip Bump, Washington Post