hl2 game engine versions (retail)

[roboticmehdi]

Hello,

I have always been confused by hl2 game engine (and data?) versions.

I mean, there are so many versions, so many names, branches, packed-unpacked, etc.

Also, backwards compatibility was broken a few times as far as I know.

Some versions are referred to by more than one name.

I could not find a clear, exact and consistent information on internet.

Also more confusion is added by thing called source sdk base versions.

Can you guys help me sort it out? Maybe a tree like structure, showing braches with points marked where compatibility broke.

I only care about HL2 games (hl2, dm, ep1, ep2, lc, etc), CS games (css, csgo) ,(and sdk base? if that is something?)

I dont care about portal or tf or left4dead or dota and others.

I am really interested in modding and making my own maps for fun.

But I cant start without knowing what the hell is going on with these versions, I feel very blind about this.

(especially need to know compatibility groups)

[Sarah]

Storyline or dates of engines we have

[roboticmehdi]

Storyline or dates of engines we have

At first I could not understand whether this is a question or a statement.

I am asking about engine versions, would be nice to have a tree structure, with point where compatibility breaks marked.

For example like this, just an example, information is not correct here:

[Temp_Acount21]

isn't supposed that source engine 2007 is the same as the Orange box source engine?