They do actually! For a 4/4 beat (4 beats per measure and the quarter note gets the beat, meaning 4 quarter notes per measure), they will move the baton straight down for 1 (the “down beat”), left (usually) for 2, right for 3, and up for 4. Different time signatures will have more or less movements, such as 3/4 time (3 beats per measure) will be down (1), left (2), and up (3).

Further, there are other movements like a wide slash left to right is a stop motion for everyone to instantly stop playing.

It wouldn’t be the first… the KGB assassinated a guy with one at least once.Bulgarian Umbrella