Slither.io is a massively multiplayer online game in which players control a snake-like creature as it glides through a virtual environment. The objective is to eat colored pellets to grow the snake, avoid collisions with other players, and ultimately become the biggest creature on the board. The game is popular due to its simple yet addictive gameplay and the ability to interact with other players in real-time. Players can customize their avatar, skins, and play in teams with friends. It was developed by Steve Howse and released in 2016. Slither.io can be played for free and on different platforms such as Android, iOS, and browsers.