Half-Life

Developer: Valve Corporation

Publisher: Sierra Studios

Release Date (US): November 19, 1998

Save Locations (Steam Version)
Steam Install Folder\SteamApps\Steam Username\Half-Life\Valve\Save\

or

Steam Install Folder\SteamApps\common\Half-Life\Valve\Save\

Save Locations (Non-Steam Version)
Half-Life\Valve\SaVe

Save Locations (Xash3DS Version)
Root of your system's SD Card\xash3d\valve\save