Can I message someone on Steam?

[Sgt_Strider]

I'm talking about Valve's Steam service. Is it possible to message other users on Steam? FYI, I haven't used Steam before so hence the question.

[Ferny84]

Yup.

You need to know their Steam ID.

[xwar]

yep.

[jeffyjaixx]

Yes.

If you join the steam community beta, once you add a person to your friends list you can chat and msg with them when you're in any steam game.