Left 4 Dead is a multiplayer cooperative first-person shooter for the PC and Xbox 360 that pits up to four players against a vast army of the undead. As the remaining survivors of an apocalyptic nightmare, your goal is to work through each level with your teammates while player and AI-controlled enemies attempt to halt your progress.

The game is free to download for 24 hours from Valve's Steam digital delivery service on May 1, 2009. Once the 24-hour period expires, the game is locked unless purchased at the retail price of $40.Kotaku: Left 4 Dead Will be Free for 24 Hours (April 29, 2009)

Valve, the developers of Left 4 Dead announced the first DLC for the game on February 5, 2009. Entitled the Survival Pack, the DLC will include an all new game mode as well as two new full versus mode campaigns.

The developers also announced that they would be releasing a software development kit for the game to PC users, enabling players to create their own campaigns to share with others. Both the DLC pack and the SDK are slated to be released in the Spring of 2009.IGN: New Left 4 Dead Content Incoming

An update for Left 4 Dead was released for the PC version of the game on January 14, 2009. The patch provides various bug fixes, including match making issues and rare achievement errors. Additionally, load times have been improved and a number of exploits have been removed.

The update also adds some tweaks and improvements to Versus mode. The HUD now shows the status of other infected players and their names appear in red in the chat window. There is now an increased chance of getting the Tank or Witch, and these now have an equal chance to spawn for both teams throughout the map. Various other changes have been made to the Hunter, Smoker, Tank and Witch.

The Xbox 360 version was patched on January 6, 2009. This update was designed to stop cheating in player-hosted matches. A group of hackers found a way to modify the game, allowing users to change a number of settings including giving players infinite health and customizing pipe bomb and molotov drop points. According to Valve, the patch prevented players from doing this in the future.Team Xbox: Left 4 Dead Hacked (December 9, 2008)

The game is comprised of four scenarios, each divided into five acts, set within a hospital, cornfield, airport and murky countryside. During the first four acts, survivors move from one safehouse to another, fighting off infected humans. Safehouses are indicated by a red door and act as a save point. Once your team reaches a safehouse, players who have died earlier in the level will respawn. During the fifth act of each scenario, players must defend their position while they wait for a getaway vehicle to arrive.

Communication between team members is enabled by quick-menu automated voice commands in the PC version and the Xbox Live headset in the Xbox 360 version.

Online and multiplayer features players able to be either one of the survivors, or one of the * Special Infected * characters whose goal is to stop the survivors.