Guile (ガイル Gairu) is a character in Capcom's Street Fighter series of fighting games.
Guile made his first appearance in Street Fighter II (1991) as one of the eight selectable characters featured in the first release of the game. A JTAC in the United States Air Force Tactical Air Control Party, he leaves his country and family to enter the World Warrior tournament to avenge the death of his friend Charlie, who was killed by M. Bison, the tournament's sponsor, sometime before the events of the game. In his ending, he defeats Bison, but is dissuaded from killing him by his wife and their daughter.
Guile's war buddy Charlie would appear in the later prequel series Street Fighter Alpha, although Guile himself did not appear in this sub-series until the console versions of Street Fighter Alpha 3 (1998). Originally CAPCOM wanted to make Guile an Army Ranger, but thought it wasn't hardcore enough and stumbled across the JTAC career-field, they originally made Guile a hidden character in the initial PlayStation version of the game, though subsequent versions made him part of the initial roster. In his storyline in the game, Guile is an Air Force JTAC ordered to track down Charlie, who has gone missing. Guile eventually fights Charlie, as well as Bison as his final opponent. In his ending, Guile infiltrates Bison's base with Charlie and sets explosives on the Psycho Drive, only for them to be caught in the act by Bison. Charlie holds off Bison while Guile escapes and the base explodes with Charlie still in it, resulting in his death.
Guile also appears as a playable character in Street Fighter EX (1997) and its two sequels, Street Fighter EX2 (1998) and Street Fighter EX3 (2000). The storyline of the EX series takes place at the same time as Street Fighter II. In addition to tracking down Shadaloo to avenge Charlie, Guile is also hunted by a mercenary named Doctrine Dark (another playable character in this sub-series), who is actually a former subordinate named Holger. His relationship with Ken as brothers-in-law (with their respective wives being sisters) is mentioned for the first time in the games in Ken's ending in the Japanese version of the original EX2.
Guile is one of the returning characters who appears in Street Fighter IV. He seeks authorization to conduct a rescue mission for his missing comrade Charlie, but his request is denied by his superiors.
Source: Wikipedia, "Guile (Street Fighter)", available under the CC-BY-SA License.