Insufficient material is an automatic draw when neither side has enough pieces to force checkmate. The clearest cases are king versus king, king and bishop versus king, and king and knight versus king — in these, checkmate is simply impossible no matter how the pieces move. When such a position appears, the game ends in a draw at once. This differs from other draws you must claim, because the game cannot continue when no legal sequence leads to mate. Knowing which endings are drawn by insufficient material helps you avoid trading down into a position you can no longer win.