Thanks for the explanation of Componant connections. I never knew any of that.
Tivo not only record things you tell it to record, it also memorizes the things you like (actors, directors, genres, keywords, etc...) and will let you know when one of those things are coming up. You can also search for things a week in advance and it will pull of whatever you are looking for and give you a full summary. And it records everything you are watching, just in case you suddenly decide you want to back up a scene or pause, or record and then play back so you can fast forward through commercials.
It will also record some things for you that it thinks you will like, though of course you need no watch it. It will record tens of hours of stuff without need for erasing anything (mine does 30 hours, others do 60 or more hours). And just in case you run out of space, it allows you to prioritize what you like most, and what you like least.
Mine comes with Direct TV, which is a satellite system. With my version, Tivo can record two programs that are on at the same time.
There are many other things Tivo does that I know I am forgetting (like short films just for Tivo users, variable recording times for things that tend to start early or go late, replay buttons, etc...).
Anyway, Tivo rocks. It's one of those few items I have bought that made me say "how did I ever get along without this" afterwards. My friends who had one all told me how great it was and I was very sceptical...until I got one. It's worth every penny.