Leeroy Jenkins originated in a World of Warcraft video shared online in 2005, showing a player shouting his own name before charging into a dungeon encounter while his guildmates were still planning. The clip spread through forums and early video sites, and Blizzard later referenced the joke in the game itself. The name stuck as internet shorthand for acting first and thinking later, which keeps the shout useful long after the original video. Short gaming clips and reaction edits still reuse it whenever someone rushes in unprepared.