The bm package defines a command \bm which makes its argument bold. The argument may be any maths object from a single symbol to an expression. This is closely related to the specification of the \boldsymbol command in AMS-LaTeX, but \bm is rather more careful in the way it does things.

The package is part of the tools bundle in the LaTeX required distribution.

The authors are David Carlisle and Frank Mittelbach. The package is Copyright © 1996-2006,2008,2009 The LaTeX Project.