Born Justin Jacob Long in Fairfield, CT, he was the second of three sons born to R. James Long, a philosophy professor at Fairfield University, and Broadway actress Wendy Lesniak. His mark on Fairfield College Preparatory School was perhaps best summed up by his yearbook superlative, "Most Likely Not to Be Seen in Class," but he continued his education at Vassar College, where he appeared in several plays, as well as the sketch comedy group Laughingstock. Long cut his college education short to pursue his acting career, which began in earnest in 1999 with the Disney live-action film "Galaxy Quest."The comedy, which cast Long as a nervous computer aficionado who aids the cast of his favorite sci-fi television series in landing a real spaceship, did much to establish his early screen persona. Despite his admission that his computer knowledge was, at best, limited, he tackled socially awkward, technologically inclined young men in comedies like "Happy Campers" (2001) and "Raising Genius" (2004). However, his best showcase during this period was as affable nerd Warren Cheswick on the television series "Ed." Though Warren endured the typical slings and arrows of high school life, the series' upbeat tone allowed him more than a few victories along the way, and even a few brushes with romance.Long also broke successfully out of the misfit mold in several features. The hit horror film "Jeepers Creepers" (2001) cast him as a wise-cracking traveler who is pursued by a humanoid monster during a cross-country trip, while the Britney Spears vehicle "Crossroads" (2002) afforded him a moment in the teen idol spotlight as the singer-turned-actress' prom date and first screen kiss. The success of both projects increased Long's profile in the feature world, and led to more prominent roles in comedies and the occasional indie drama. Though Long's post-"Ed" characters continued to toe the oddball line, his comic timing gradually elevated him from sidekick status to second lead and even starring roles in films with such box office champs as Ben Stiller and Lindsay Lohan. He was a member of Vince Vaughn's hapless "Average Joe" team in Stiller's broad comedy "Dodgeball: A True Underdog Story" (2004), then took top billing as a slacker biding his time as a server at a greasy spoon in "Waiting " (2005) with Ryan Reynolds and Dane Cook. The Disney comedy "Herbie: Fully Loaded" (2005) gave him another shot at screen romance, this time opposite Lohan, while the lowbrow "Sasquatch Gang" (2006) allowed him to stretch his comedy skills as a dim-witted opportunist seeking to cash in on an alleged Bigfoot sighting. He reunited with Vaughn for "The Break-Up" in 2006 before landing his second starring role in "Accepted" (2006). The comedy cast him as a scheming high schooler who creates his own college to distract his parents from his failing grades. Though each subsequent film helped make Long more visible in the entertainment industry, it was a series of television commercials that truly cemented his place on the post-millennial pop culture map.In 2006, Long was partnered with humorist John Hodgman in a series of extremely well-received television ads for Apple computers. The "Get a Mac" campaign followed a basic and very simplistic formula: the casual-looking Long and a suit-and-tie-wearing Hodgman would introduce themselves as a Mac and a PC, respectively, after which Hodgman would attempt and fail to convince viewers that his allegedly limited capacity could not only equal but best Long. The seemingly improvised spots gave millions of viewers their introduction to Long's comic abilities; however, unlike many television pitchmen, the commercials did not appear to hamper his feature career in the least. If anything, they boosted his profile considerably in 2007, which saw him co-starring with Bruce Willis and finding a place in Judd Apatow's cabal of comedy players.The blockbuster "Live Free or Die Hard" (2007) cast him again as a computer jockey, though this time with the skills to aid Willis' indestructible cop John McClain in stopping a terrorist plot to shut down the United States' communication systems. Long also lent his voice to lead chipmunk Alvin in the live-action film version of the long-running cartoon series "Alvin and the Chipmunks" (2007) before giving an amusing impersonation of "Sgt. Pepper"-era George Harrison in the Apatow-produced biopic parody "Walk Hard: The Dewey Cox Story" (2007). The year 2008 saw Long firmly in comedy mode, with appearances in features ranging from the critically reviled "Strange Wilderness" to Kevin Smith's comedy hit "Zack and Miri Make a Porno," where he broke amusingly from type as a gay adult film star who helps inspire Seth Rogen and Elizabeth Banks to pursue their own fortune in pornography.The year 2009 was one of Long's busiest to date, with roles in films by the likes of Sam Raimi ("Drag Me to Hell"), Miguel Arteta ("Youth in Revolt") and Cheryl Hines ("Serious Moonlight"), as well as "Alvin and the Chipmunks: The Squeakuel" on deck. The most high-profile of these, however, was "He's Just Not That Into You" (2009), Ken Kwapis' ensemble comedy based on the best-selling book by Greg Behrendt. Though Long had a supporting role as a savvy bartender who aids the lovelorn Ginnifer Goodwin - his onetime "Ed" co-star - he gained front page status for his brief 2008 off-screen romance with the film's star and co-producer, Drew Barrymore.Meanwhile, Long had a series of voiceover roles in animated films like "Battle for Terra" (2009), "Planet 51" (2009) and "Alvin and the Chipmunks: The Squeakquel" (2009), before returning to live action to co-star opposite Barrymore in the romantic comedy "Going the Distance" (2010). After another voice role for "Alpha and Omega" (2010) and reprising Alvin for "Alvin and the Chipmunks: Chip-Wrecked" (2011), Long earned critical praise for his recurring role as a music teacher who enters a complicated romance with the bubbly Jess (Zooey Deschanel) on the hit sitcom "New Girl" (Fox, 2011-). Long's screen career cooled during this period, with films like the romantic comedy "A Case of You" (2013) and the parody Steve Jobs biopic "iSteve" (2013) attracting little attention, but his leading role in Kevin Smith's horror comedy hit "Tusk" (2014) reminded audiences of his charm in even the most unlikely projects.