Source (game engine)

Source
Source
Developer(s)	Valve
Initial release	October 2004
Repository	source-sdk-2013 on GitHub
Written in	C++
Middleware	Havok
Predecessor	GoldSrc
Successor	Source 2
License	Proprietary
Website	developer.valvesoftware.com/wiki/SDK2013_GettingStarted

Source is a 3D game engine developed by Valve. It debuted as the successor to GoldSrc in 2004 with the releases of Half-Life: Source, Counter-Strike: Source, and Half-Life 2. Valve used Source in many of their games in the following years, including Team Fortress 2, Counter-Strike: Global Offensive, Dota 2, and the Portal and Left 4 Dead franchises. Other notable third-party games using Source include most games in the Titanfall franchise, Vampire: The Masquerade – Bloodlines, Dear Esther, The Stanley Parable and Garry’s Mod. Valve released incremental updates to Source before it was succeeded by Source 2 in 2015.