In the style of contemporaries like Eugene Mirman and Zach Galifianakis, Martin stretches the boundaries of the form into something resembling a form of Borscht Belt performance art, as if Laurie Anderson's primary influences had been Steven Wright and Peter Sellers. Incorporating musical instruments, props, and video into his otherwise standard on-stage act, Martin's primary on-stage persona is that of a naïve youngster reminiscent of '80s cult comic Emo Phillips, but not nearly so deliberately annoying.

Born in New York City in 1973 (although he looks about 19 with his trademark John Lennon circa Rubber Soul shaggy pudding bowl haircut) into a close-knit Greek Orthodox family, Martin graduated from Yale University but dropped out of law school at NYU to pursue comedy. After his 2003 one-man show If I... won an award at the prestigious Edinburgh Fringe Festival, one of the world's best showcases for alternative comedians, Martin spent a period on the writing staff at Late Night with Conan O'Brien while preparing his first TV comedy special. That 2004 special, Comedy Central Presents: Demetri Martin, featured acting roles by Martin's mother and grandmother; his grandmother also plays a featured role in Martin's first CD and DVD, These Are Jokes, released in September 2006. Also in 2006, Martin scored a major TV gig on Comedy Central's The Daily Show, as part of the same infusion of fresh faces that included John Hodgman and Dave Gorman; Martin's role is that of the giddily clueless "trend reporter," a loving sendup of clichés about The Daily Show's average college-aged viewer.

In 2009 he launched the sketch comedy series Important Things with Demetri Martin on Comedy Central with a second, final season airing in 2010. Between the seasons, Martin starred as the main character in Ang Lee's 2009 film Taking Woodstock. He returned to comedy albums and the Comedy Central record label in 2012 with the aptly titled Standup Comedian. ~ Stewart Mason