There are two clocks during a game. One clock for each player. The clock counts down only when it is a player's turn to move. When a clock reaches zero, then the game ends as a loss for that player.
2|0 means the clock is set at 2 minutes for each player.
2|1 means the clock is set at 2 minutes for each player and after every move 1 second is added to that player's clock.
So for example 10|3 would mean 10 minutes on the clock, and after each of your moves you gain 3 seconds.
In that example if we wanted to calculate the maximum possible time for a 40 move game (assuming they both ran out of time on move 40 which is not possible in a normal game) the total time for the game would be 10+10 (because 10 minutes for each player) plus 40*3 seconds for each player. So 10 minutes + 10 minutes + 120 seconds + 120 seconds = 24 total minutes in a 40 move game.
In a 2|0 game, the maximum possible time is 2 + 2 = 4 total minutes.
what are the rules for timings and what is 2|1, 1min etc.