that can stop someone else copying data on a disc i've made? and how would this be done plz?

You could close the disk - but then you couldn't add to it either.

I think I may have misunderstood your post. You want the data on the disk to be inaccessible? What I have done previously was to burn the data as part of a password protected zip file. There may be a better way but I don't know it.