How do cheat codes work?

Question

Many of us would have used cheat codes at some point in our lives while playing a PC game. I was just wondering how does that work?

Edit: Adding onto this, do trainers work the same way?

In: Technology

Answer 1

Im gonna use gta 4 as an example. They are coded special sequences that if pressed in the right order and in a certain time something happens. It’s kind of like self hacking.