Eli5: What is the real difference between analog and digital?

Question

I tried looking it up, and my brain just wasn’t making sense of it, but I haven’t had coffee yet so.

In: 0

Answer 1

Analog comes from analogous.

> comparable in certain respects

So if the representation of something is comparable to the actual thing, it’s analog.

For example, a vinyl record is an analog recording of sound. The wiggles in the grooves of the record are the exact same wiggles of the actual sound wave. The grooves are a representation of the sound, and they’re directly comparable to the actual sound waves. The grooves are *analogous* to the actual sound waves.

Meanwhile, a CD is a digital recording of sound. A CD has a bunch of pits and lands (aka 0s and 1s) etched into it. Not at all comparable to an actual sound wave. You need a key to decode it to get the actual sound wave information out of it. The pits and lands are not analogous to the actual sound waves.