In my science class, we're currently doing a unit on chemistry. Today we pretty much went over the structure of an atom, and the teacher was talking about the electron levels. She said "You can have up to 18 electrons in the third ring but after eight electrons in that third ring you get into sublevels ." Can someone explain the sublevels in the electron field? Basically, I'd like information on atomic structure. I know that within the nucleus there are protons and neutrons, and surrounding them is the electron cloud. What I want to know is how the sublevels within the electron cloud are structured and what they are.