Picture Probs

Sometimes instead of doing laundry (I lie. It should've said every time) I move stuff around and take pictures and sit on photoshop for hours because I am still learning the tricks of picture manipulations. I feel like I am getting better but I stare myself blind sometimes. Like my biggest photoshop Q is: white. How white is too white?! How does exposure and taking the black out of white effect a picture? I can't seem to figure it out.
BIG questions and BIG topics for a Monday.. Now excuse me. I hear the washing machine calling my name and luckily in laundry land nothing is ever too white!