Half-Life 1998 - the Half-Life - was very different to the preview alpha build of Half-Life 1997. And now you can see it for yourself.
A demo build of 1997 alpha found on a disc intended for journalists at the time, apparently, has been shared on the internet by Reddit user Jackaljayzer (via ValveTime).
"To play the alpha," instructs the site, "delete or renamed the '...\Half-Life 0.52\Half-Life\Opengl32.dll' file and then run '...\Half-Life 0.52\Half-Life\enginegl.exe'."
Wouldn't it be fun if this were the start of a Half-Life 3 ARG? That's the whisper, although it's probably nothing.