There should be lessons here on basic chord construction and almost anything. I know in the beginners guide there should be a starting guide to theory.

Major and Minor are types of chords. A sharp is relative to pitch so you can have Cmajor but up one fret is C#major. Not all chords are Major or Minor but you can add a note to either to get something like Cmaj7. The 7 being a note you added. Try starting here. http://www.guitartricks.com/lesson.php?input=7643&s_id=65