The importance of charm decays in the context of flavor is motivated.
A theory overview on recent developments in leptonic and semileptonic decays, hadronic two-body decays, and rare decays is presented.
Standard Model (SM) predictions as well as tests of the SM are pointed out, {\it e.g.}~how to discover direct CP violation in charm decays and how to search for physics beyond the SM.
Differences between rare charm and beauty decays are discussed.