xbmc stream to internet connectivity device?

Hi all. I am super duper new to xbmc and I been reading here and there and just got it all set up on my personal computer, its a nice i7 2nd gen 16GB desktop. I am wondering what can xbmc actually do.

Can I like turn it ON on my computer and stream movies to my laptop in another room? To my XBOX? Or my TV? Like, can I stream it to anything else or the xbmc has to bee installed in each device and have all the movies in each computer for me to see it on different locations in my house?

Thanks.

EDIT: As I read more and more, I just found out you can stream to other computer and laptops. I just cant seem to find out how this is done. Hope I can get some help