Help with bouquets

Can anyone point me to a tutorial on bouquets?

I bought a system some months ago with bouquets already set up, but I'm not really sure how they work. I would like to start from scratch and add my own as I need them.

Can I just delete (or move) my bouquets and create them one by one?

And where can I find a description of the format of "/etc/enigma2/bouquets.tv"?

I have a TechnoMate TM-NANO 2 Super running OpenATV.

It is a used unit so am not sure how it was set up. I'd like to start again from scratch with bouquets but am not sure what would happen if I delete (move) my existing bouquets. I'll look at your suggestion and see if it helps.