what is half life source?

[mega-64]

I have Half life 2 and it has half life source with it.
how do i use it .
Also how do i put the first half life on my steam account?

 

[Didou]

Half-Life source is the original Half-Life game with certain engine updates brought by the Source Engine (most notably the water effects). I'm not sure if it adds much more then just a few visual extras though.

As for the 2nd question, isn't that explained in the manual ? I only have the Steam version myself so I can't help there.