.mc is the Internet country code top-level domain (ccTLD) for Monaco.

An M.C. is a Master of Ceremonies.

MC++ may refer to:

• Managed Extensions for C++, also µC++ and uC++, an extension of the C++ programming language designed for concurrent programming
• MC Plus+, an Iranian-American Nerdcore hip hop rapper
• MC++ (McCormick relaxation library): a C++ library employing operator overloading to perform interval arithmetic, McCormick relaxation, and related functions.

A master of ceremonies (also used in its abbreviated forms MC or emcee) or compère [commère being the female form] is the official host of a staged event or similar performance.