What is Don't pass?
Don't pass is the craps bet against the shooter, winning on 2 or 3 at the come-out, or if a 7 is rolled before the point; it carries a house edge of about 1.36%.
The bet loses on a come-out 7 or 11 and wins on 2 or 3. A come-out 12 is a push, which is shown on the layout as 'bar 12'. That push is what gives the house its edge, since without it the bet would favour the player. Once a point is set, don't pass wins if a 7 comes before the point.
At about 1.36%, don't pass has a marginally lower edge than the pass line. Players can also lay odds behind it, which carries no house edge.
Betting the don't side is sometimes considered unsociable at the table because it wins when most players lose. Don't pass bets can be removed after a point is set, because at that stage they are favourable to the bettor, though doing so gives up that advantage. Casinos treat bar 2 and bar 12 versions differently, so the bar number is printed on the layout.