How do you determine the major product? I have been going over questions from the database and just when I think I’m doing it right I get the question wrong. Could you please clarify on that. (The major product is either lowest in energy (for equilibrium conditions), or the fastest forming product - GS).

Could we please go over what exactly a carbocation is?  It comes up a lot in class and I just wanted to make sure I know what it exactly is.  Thank you! (It is a particle with a carbon with the formal charge +1 - GS).