Types of live chess

Hey,

I'm new to Chess.com and when joining a game, I can choose 10 min, 5 min, 3 min etc which is clear, but I do not understand what 2|1 means, or 15|10?

R

2/1 means 2 minutes per person, with a 1 second increment after (I think it's fater, not before) each move. And Likewise, 15/10 means 15 minutes for each person, with a 10 second increment per move.

The first number is the base length of the game, i.e 2/1 is a two minute game.  The second number is the increment, i.e. the time you gain after each move.  So in a 15/10 game, the game is 15 minutes but each player gains 10 sec. after each move.  I you spend 5 sec. on your first move, you now have 15 min. 10 sec. left, etc.

I see, thanks!

The games with the increment are real fun.