Philip Edward Hartman (b. Philip Edward Hartmann; September 24, 1948 - May 28, 1998) was a Canadian-American actor, comedian, and voice actor. He provided the of voiced several characters on The Simpsons. Troy McClure and Lionel Hutz were his most popular. Matt Groening and the production crew and other voice actors expressed he was fun to work with. Before Billy West, he was supposed to voice Zapp Brannigan, but unfortunately, he was murdered before the show began. In his memory, they named Fry after him, and Billy West, out of respect, tweaked his own voice to match his tone for Zapp.

Wikipedia has a page on Phil Hartman