Phrase in FAQ?

Now, I know Black Mesa is free, but what about this?

As long as you have Steam installed on your computer, Black Mesa will cost you nothing.

Now, what happens if I don’t have Steam installed?
Steam is a free program, I don’t see what they are
trying to say here.

Any advice would be helpful.

Either way, Black mesa is free. Even if they wanted to charge for it, that’d be illegal. So yeah, BM is free.

I think you need a Steam account in order to download Black Mesa. If you don’t have Steam you can’t play Black Mesa.

Yeah, you’ve read WAY too much into that.

Founded in 2004, Leakfree.org became one of the first online communities dedicated to Valve’s Source engine development. It is more famously known for the formation of Black Mesa: Source under the 'Leakfree Modification Team' handle in September 2004.