An overview on decision diagrams (DDs) is given. DDs are the state-of-
the-art data structure in verification and logic synthesis. They are w
idely used, and are integrated into commercial tools. The overview is
incomplete in the sense that not all DDs are considered, but the autho
rs mention the most important DDs, with practical relevance. DDs with
special emphasis on the aspect of function representation at bit-level
and word-level are considered.