flOw is an abstract arcade-style organism-evolution video game available for the PC, Playstation 3 and PSP. Originally developed as a thesis by Jenova Chen of University of Southern California, flOw has sparked a sizable following ever since it's initial release as a PC browser game on April 14th, 2006. Chen went on to form ThatGameCompany, which has also developed the critically-acclaimed Flower and Cloud.

flOw has no real narrative, instead focusing on a simple organism which evolves and transforms as it consumes other organisms. The game is set in a luminous but simplistic primordial ocean, where the player can transition to different colored tiers of the ocean world.

The arcade-style gameplay of flOw involves the player manipulating a small organism and moving it around to consume other organisms on the screen. As the player's organism consumes more and more, it's shape and size begin to change. Consistently eating different shaped organisms will result in a variety of appearances for the player's avatar. Once the player feels they have exhausted one tier of the ocean world, they are free to move on through portals, or even come back, at their own pace.

The simple presentation and gameplay of flOw provide players with a light but intuitive experience, where the difficulty of the game is measured by the rate of a player's real-time progress.