What is the difference between half life and half life source

Half Life is the original game released in the late 90's. This also include the popular multi-player mod Counter Strike.
'Source' is the name of the new game engine that was designed to run it's sequel Half-Life 2. The updated version of Counter Strike that uses this engine is called CS:Source.
'Half Life: Source' is a remake of the original Half Life using the updated engine.
[stormroad says] [basicley its the a little better quallity of the game but not half life 2 quallity]