2 is not forcing. 2 after a NT response is Stayman. Jumps in new suits show good strong jump overcalls. Jump cue shows a mammoth takeout double with a void. Jump to 2NT is a huge hand, 22-23 or so.
Raises show extra values, either by way of fit, shape, or high card.
They promise at least 3-card support, usually four. New suits after a simple suit response are five-card suits and don't promise any extra values. They are not forcing. Cues after simple suit or 1NT responses are very strong. Herbert Negatives apply.