Engine settings and knowledge

So I've been strolling around here and I've realized there are too many engine related terms (MultiPV, contempt, move overhead, etc.) I do not understand, google is of little use, do you guys know of any place to read about this stuff? Could someone explain the not so basic not so advanced perks of engines?

Well, I typed stuff but there was an error and chess.com ate my post.

MultiPV is showing multiple lines. It's useful because you can see if an advantage is stable (all moves are about the same eval) or if the next move is critical (one move is much better than the others). The engine reaches a high depth slower (it can't go as deep because it's paying attention to e.g. 3 lines instead of 1).

It can also help you see more practical ways to play a position (some engine moves are too technical or risky).

Contempt is where the engine wont necessarily play the move it thinks is best against you, because it's holding you in contempt

It will avoid trading pieces, locking the structure, that sort of thing. This is useful in handicap matches (otherwise it's sometimes really easy to beat a strong engine a piece up, because it will just trade everything). It's also useful for analyzing positions where you're purposefully playing down (like a gambit) for the sake of practical chances. So if you're analyzing a gambit line the engine doesn't really like, and if you intend to play this gambit OTB, it's probably best to have at least some contempt value turned on.

Move overhead is just the time it takes to transfer the move. This isn't useful unless you're using an engine to play online (which is allowed on some sites) or if you're setting up an engine vs engine match were two separate computer setups are playing each other. Basically the engine, internally, thinks it can move in 0.0 seconds... but of course this is not true. It takes a fraction of a second to transfer its move. So it can lose on time when it thinks it still has 0.2 seconds left. But if you set move overhead to 0.2 second then that wouldn't have happened.

Hash table is one you didn't ask about, but it's important. It's the memory you give to the engine to store the result of its calculation. So for example if you gave it only 100 megabytes then it would be useless to let it think for an hour, because it wouldn't know what moves it has and hasn't looked at. It would just calculate in circles.

That one I did know and understood, I figured it helped to avoid recalculating lines that had already been considered, I try and give 4 Gb to my engines.

What about resseting them? For how long does an engine store its hash tables? Is it more tailored for a match or do they persist after an analysis task?

Thanks a lot for the replies!

Can that help solve a puzzle which contains a move that the engine probably wouldn't consider by itself?

Yeah, it's nice for puzzles because you can quickly see if your move was one of the top moves, and if it was any good

You know, sometimes the 2nd best move is mate in 8, but sometimes the 2nd best move is only +1.00 instead of +6.34

Yeah, you can save hash or something... I think. Not sure.

I found this link that will probably be useful for you

https://komodochess.com/store/pages.php?cmsid=14

Not sure if it's programmed into the engine or intrrface, but the latest versions of Fritz, Komodo, and Houdini, using the Fritz interface, all have adaptive technology. So the engine will adapt to your playing level. 

As far as setting up a chess engine, there are forums on the internet dedicated to engine play and programming.

Thanks again!