Unrelated to the Mac OS X version that was ultimately released by Valve in 2013, the Macintosh (Mac OS) port of Half-Life was announced to be in development by Logicware on April 23, 1999. Both games were later ported to Mac OS X and Linux and released in 2013. The multiplayer portion was released in another package called Half-Life Deathmatch: Source in 2005. According to Doug Lombardi, it began as an experiment to see what modders would experience if they attempted to bring their Half-Life mods forward to Source. It uses the special effects and physics engine features of the new engine. It was released along with Half-Life 2 on November 16, 2004. Half-Life: Source is a direct port of Half-Life to the Source engine.
