2. You have a tremendous hand, good enough to force to game with a natural jump shift. This shows 4, longer clubs and nearly a strong 2 opener. Your partner cannot pass until at least game is reached.

4. This is not a closeout bid! Your partner might have only 6 points, and you announced that opposite so little, you are willing to contract for 10 tricks! This shows a huge hand, like the one you have. With 4-card support and a little less you would raise to only 3 invitational. With 4-card support and a minimum opener, you would have raised to only 2.

2. This is a reverse, showing at least 16 or 17. You are worth it. It shows 4 hearts and longer diamonds and an unbalanced hand. It is forcing 1 round (but not to game). 

Note: Don't jump and reverse (3).

2. You have a beautiful 2-suiter, but not enough to force to game with a jump-shift. Picture poor partner with, say:

 Q10765  
 2  
 KJ32  
 842
 (with that, partner can pass 2, which isn't forcing).

2NT. Regardless of what 1NT means (old fashioned 6-10 or modern forcing or semi-forcing), this 2NT rebid shows 18-19 balanced. There is no need to jump to 3NT (which really should show something like this: AKQJ32  A2  K3  J32).

3NT. A jump to 3NT doesn't show a balanced hand. It shows a source of tricks and some stuff elsewhere.  You don't have to have all the suits completely stopped.