backing-up files

hi there,
i have a clients and want their important files to back-up to another computer. they have 14 computers and all networked. 1 computer is running in windows 2000 NT, where their files want to store to. and rests are workstation running in windows xp.
how do i configure all files in workstation to automatically back-up it to windows 2000 NT computer everyday? is there any programs to install? please help me do this. tnx i advance!