Osu

Osu may refer to more than one geographic or cultural entity. In geography, Osu is a district of Accra, the capital of Ghana, located along the southern coast in the Greater Accra Region. The area encompasses residential, commercial, and entertainment zones and is known for busy markets, nightlife corridors, and historical sites. A notable landmark is the Osu Castle, officially Fort Christiansborg, which sits on a waterfront promontory and has played a significant role in the history of the region.

In gaming and digital culture, osu! is a free-to-play rhythm game created by developer Dean “peppy” Tsai. The project originated as a Windows application in 2007 and has since expanded to multiple platforms, including macOS, Linux, iOS, and Android. The core gameplay involves timing-based inputs to beatmaps set to music, demanding precision and rhythm.

osu! features four main modes: osu!standard (the original mode with circle notes and sliders), taiko, catch the beat, and osu!mania. Beatmaps—user-created timing maps—are shared online and rated for difficulty and playability. The game supports online rankings, multiplayer modes, and regular community tournaments, contributing to a large, active community of players and creators.

The term Osu is thus used to refer to both a district in Ghana and the widely known rhythm game osu!, though the official stylization for the game is osu!.