system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why does my key fob only work for my car?

When I press "unlock" why does it only unlock my car? Why don't other cars react to my key fob? Are they all on different frequencies or what?
gpt
the very first ones actually had a keypad on them, and you entered a code to unlock it remotely. these days, that's done on the inside. when you press the button, it sends a unique digital identification code through the radio frequency editor that's in there. you were pretty close.