Intermediate and newcomer players - sharpen your game with this series of tutorials. You can browse the index by topic, or read them in order. Learn even more at ACBL's Learn page.
The humble finesse is the first thing we learn, and we also learn that some finesses win, some lose. Later we learn that some finesses are purely for practice and serve no useful purpose. Here is a case in point.
As South you open 1♠, and your left-hand opponent jumps in with a jump overcall to 2NT. What does this bid mean?