This article is incomplete and waiting on someone to expand it.

Release stream

osu! has a few release streams, or game client versions, that receive updates at different rates. In order to catch potential issues early, new features and changes are put into preview versions before making their way to the stable client.

Release stream Notes
Stable Current, most popular version; feature-locked; receives updates after Beta
Beta Receives updates after Cutting Edge; feature-locked
Cutting Edge Receives newest updates; feature-locked
Lazer Rewritten game client; most active in development with many differences and new features.