Half-Life: Uplink

Half-Life: Uplink is a demo version of the first-person shooter computer game Half-Life by Valve from 1998. Uplink contains many of the familiar enemies, characters and weapons from the main game, but unlike the first Half-Life demo and the Half-Life 2 demo, the setting and scenario in this demo do not appear in Half-Life. The Uplink chapters were cut during the development phase of Half-Life and inserted roughly before or during the Lambda Core chapter; however, they were heavily reworked for the demo release. Uplink also contains the same Hazard Course as the full version of Half-Life. It was also included on the "Official PlayStation Magazine Disc 57" as a bonus that could be unlocked by entering a cheat into the PS2 version of Half-Life and swapping the discs.