Street Fighter II (1991): The Arcade Game That Invented Modern Fighting Games
Eight fighters, six buttons and an accidental combo system turned arcades into competitive arenas.

In 1991, Capcom released Street Fighter II: The World Warrior in arcades. The first Street Fighter had been a modest hit; the sequel became a phenomenon.
What changed
- Eight playable fighters, each with distinct moves and personalities, from Ryu and Ken to Chun-Li and Guile.
- Six-button controls with light, medium and heavy punches and kicks.
- Special moves performed with joystick motions, such as the Hadouken.
The accidental combo
Players found they could cancel the recovery of one attack into another, linking hits the opponent could not escape. That combo discovery was not planned, but Capcom embraced it, and combos became the foundation of every fighting game since.
Arcades as arenas
Two players side by side, one coin to challenge the winner: Street Fighter II turned arcades into local competition, from Japanese game centres to Korean 오락실. That culture led to tournaments such as Evo and today's browser and online fighting scenes, including our own ArcadeChain.
Reference: Wikipedia, Street Fighter II and Combo (video games).