I am learning how to use Stockfish to analyze my games, and I had a question on how to understand Stockfish's output.
Consider the screenshot when I request stockfish 12 to annotate my games inside SCID.
As the number in the square brackets refers approximately to the "advantage" (however that may be defined) I would have if I followed the moves in the suggested lines. This is why lines that have the same initial set of moves, have a different score when they diverge e.g. lines 9 and 10 in the output which have scores of 1.12 and 1.25 respectively.
But what I want to know is in what order does Stockfish suggest the various lines of output. Notice that the various lines list advantages not necessarily in increasing order. Here are my questions.
Is the program, brute force checking through all possible lines of play (up to a prescribed depth) by both players and then suggesting the best lines of play found till now?
Does it suggest what the advantage would be for the strongest lines of play i.e. "perfect" play for both black and white would be N number of moves down the line given a particular move by White?
Basically, the fact I am asking these two questions suggests, that I approximately (but not completely) understand what Stockfish is outputting. Sure, SCID annotates via arrows the best move at each position. But what EXACTLY are assumptions for each line of play that Stockfish is outputting? Clearly, it is not outputting disastrous lines of play, so it is not listing the advantages for ALL possible lines of play up to a certain depth.
Also, the lines are numbered from 1 to 21 in the output above, but why is line 2 missing?! The image has not been edited!