Strong bread flour, a little yeast (you can get packets of dried yeast that make it easier), water, maybe a little salt and for variations of types of bread anything else you like to add.
You can also get packets of bread mix that you just add water to, but they work out a little more expensive, unless you can get them on special offer days.
Throw it all in the bowl, close the lid, tell it which type of loaf you are making, most machines even have a timer so you can set it up before you go to bed and have it come on and make the bread so thats its ready for when you want some for breakfast