Post
The game secretly remembers your button press so it executes the instant it becomes possible.
Input buffering is when a game stores your input during a window where it can't execute yet, then plays it as soon as it can. Press the attack button 3 frames before your dodge animation ends? The game queues that attack and fires it on the first available frame. Without buffering, you'd need frame-perfect timing for every action, and games would feel unresponsive. Fighting games typically have a buffer window of 3-10 frames. Too short and the game feels stiff. Too long and you get accidental inputs you didn't want.
Example
Super Smash Bros. Ultimate has a generous 9-frame input buffer, which is both a blessing and a curse. It makes the game accessible but competitive players often complain about 'buffer fails' -- accidental moves that come out because they pressed a button slightly too early during a previous animation.
Why it matters
Input buffering is why some games feel effortlessly responsive and others feel like you're fighting the controls. For competitive players, understanding buffer windows is essential for consistent execution. For devs, buffer tuning is a critical accessibility vs precision tradeoff.
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