  This article introduces a new term "splint" and classifies the splints of the
classical root systems. The motivation comes from representation theory of
semisimple Lie algebras. In a few instances, splints play a role in determining
branching rules of a module over a complex semisimple Lie algebra when
restricted to a subalgebra. In these particular cases, the set of submodules
with respect to the subalgebra themselves may be regarded as the character of
another Lie algebra.
