Rob McElhenney
Robert McElhenney III ( MAK-əl-hen-ee; born April 14, 1977), also known professionally as Rob Mac, is an American actor, screenwriter, producer, director, and businessman. He is best known for his role as Mac on the FX/FXX comedy series It's Always Sunny in Philadelphia (2005–present), a show he created and co-developed with Charlie Day and Glenn Howerton and on which he continues to serve as an executive producer and writer.