Dealer button heads up

In heads up poker holdem, the dealer button has the small blind and the other player has the big blind. The dealer button gets dealt the first card (he is the small blind), then the big blind gets his first card.

Then after the players get their cards, the preflop betting starts with the small blind (the dealer button). After the flop is shown, now the player on the dealer button is last to act. So preflop the dealer has to act first and gets the small blind, after the flop - flop, turn and river betting - the dealer is second to act. The reason this is like this is because if the dealer button had the big blind, it would be too much power - the dealer would have the big blind (quite a lot of money in) plus position for every betting round. This would make heads up play really tight with the small blind only playing with premium hands (in which case the dealer would most likely fold). So by giving the small blind to the dealer button, it is more balanced and a better game.