The player controls a dot, square, or object on a bordered plane. As it moves forward, it leaves a trail behind, resembling a moving snake. In some games the end of the trail is in a fixed position, so the snake continually gets longer as it moves. In another common scheme the snake has a specific length, so there is a moving tail a fixed number of units away from the head. The player loses when the snake runs into the screen border, a trail, or another obstacle. The Snake concept comes in two major variants: In the first, which is most often a two-player game, there are multiple snakes on the playfield. Each player attempts to block the other so he or she runs into an existing trail and loses. Surround for the Atari 2600 is an example of this type. The Light Cycles segment of the Tron arcade game is a single-player version, where the other "snakes" are AI controlled. In the second variant, a sole player attempts to eat objects by running into them with the head of the snake. Each object eaten makes the snake longer, so maneuvering is progressively more difficult. Examples: Nibbler, Snake Byte.
This is a type specimen showing animated svg within OpenType fonts. You only see static type above? You might consider firing up Firefox (version 26+) for the full glory. The text above is set in OpenType fonts with embedded svg. Things might change but as of this writing (November 2014) the format is supported by Firefox only.
Click in the text and type away to test it yourself!
Why use color fonts only for emoji? Color is more than a pile of poo and red hearts! You can find some information about the format and how the fonts were built on this site.