What is a Heuristic Function

Question

Can someone explain in very simple words what it is. Also provide an example. So for example if u have to find the heuristic function of something how is it supposed to look

Answer 1

From wiki

A heuristic function, or simply a heuristic, is a function that ranks alternatives in search algorithms at each branching step based on available information to decide which branch to follow.

I.e. in chess, a Heuristic Function can rule out possible moves that will lead to a worse position (or even loss) for a player and not further analyze the following moves since the result will not get any better.

Doing so the function can search more moves in a shorter time period since it doesn't waste time looking at bad moves.