You need to buy Portal in order to play the mod Portal: Prelude.
no you cannot anymore because portal prelude was terminated
If you want to play the game on a PC or a Mac, yes.
Urm... you just buy Portal 2 from Steam and then play it...
Portal does not have online like Black Ops and Halo, etc. Portal 2 does have a Co-op though so you can play with friends.
No, Portal is for PC only. Portal 2 is for PS3,Xbox 360,and PC. Plus it would suck on PSP.
You need a PS2 to play the games not a PC
It's for PC and PC only.
You need a PC with two keyboard and two mouse ports to have any chance of its hosting multi-players with any chance of success. It is still not a recommended game to play with more than one player at a time.
You need a emulator to play the Playstation Game on a PC
Yes. Portal 2 is on Xbox 360, PS3 and PC.
No, Portal 2 is also out for PS3 and PC.
No Portal 2 is for PC, Xbox 360 and PS3.