Question About Website Hosting

Hi all

I have a couple of questions about website space and domains, hopefully someone can answer them.

I have a couple of friends who want websites made for them so firstly they would need to buy the domain name, that bit im clear on. I already have a site and my own webspace (with 1and1.co.uk, 800mb of space). Am i able to use that to host my friends work and stuff for their websites or would they need to buy their own space with their domain?

I have no idea what forum this should go in.

Thanks