Half-Life (series)

Half-Life is a series of video games created by Valve Corporation. The player plays as a character named Gordon Freeman, who is a survivor of a terrible accident at the Black Mesa Science Research Company. A group of scientists make a portal to another dimension, and accidentally let in many alien monsters that start killing everyone.
In the first game, "Half-Life", made in 1998, you play through this disaster and try to escape.
In 2004, the sequel, "Half-Life 2", was released. "Half-Life 2" was followed by two expansions, ' and '.
A related game, "Portal", was released in 2007 and takes place in the same universe. "Portal", "Half-Life 2", "Half-Life 2: Episode One", "Half-Life 2: Episode Two", and "Team Fortress" (an unrelated game) were put together into one package for sale in 2007. This package is known as "The Orange Box".