What do BB, SB, BTN, CO, MP, EP mean?

Poker Copilot tracks some statistics by position. For example, you can see “VPIP” by position:

The positions are defined as follows for 10-player tables:

• BB – big blind
• SB – small blind
• BTN – button
• CO – cut-off (the seat to the right of the button)
• MP – “middle position”: the three seats to the right of the cut-off.
• EP – “early position”, the three seats to the right of middle position. These are the first players to act pre-flop. On 9-max tables, there are only two seats in early position.

Here’s a diagram showing the positions on a 10-max table:

Here are the positions on a 9-max table:

For 6-max tables, the definitions are:

• BB – big blind
• SB – small blind
• BTN – button
• CO – cut-off (the seat to the right of the button)
• MP – “middle position”: the seat to the right of the cut-off.
• EP – “early position”, also known as UTG (“under the gun”). The first player to act, pre-flop.
  

Why you should care about the positional stats.

Poker is a game of limited information. The later you have to act, the more information you get, and therefore you have an advantage over early position.

In early position players have to decide whether to call, fold, or raise without having any idea about what cards other players have. By the time the action gets to the button, several players have had to make actions already, giving the button more information.

This positional advantage continues on the flop, the turn, and the river. The button is always the last to act (excepting the blinds pre-flop), and therefore always gets to see how the other players act.

A good poker player knows about this positional advantage, and uses it wisely.