Why is this Attribution-ShareAlike license a good thing?
It’s good because it allows other people to more easily share and build on your work. Furthermore, if they create new material based on your original, the new works must carry the same license, meaning that those new works can be used by you, and others, for further creative efforts. It spares others from having to track you down at some distant time, negotiate for permissions, get a license in writing, etc. The license acts sort of like a virus, but a good one that enables greater public benefit by reducing complex barriers.
