The knights and the bishops are called the minor pieces, as they are typically weaker than queens and rooks.

The term minor pieces in chess refers to the bishops and knights collectively. They have this name because they are generally weaker than the so-called major pieces (rooks and queens). This is reflected in the widely-used point system that provides players with a rough guideline as to the relative values of the pieces: pawn 1, knight 3, bishop 3, rook 5, queen 9.