Attribution means:
You let others copy, distribute, display, and perform your copyrighted work - and derivative works based upon it - but only if they give you credit. 
Noncommercial means:
You let others copy, distribute, display, and perform your work - and derivative works based upon it - but for noncommercial purposes only.
No Derivative Works means:
You let others copy, distribute, display, and perform only verbatim copies of your work, not derivative works based upon it.
Share Alike means:
You allow others to distribute derivative works only under a license identical to the license that governs your work.
is a license that allows creators to maintain a copyright while allowing users the right to reuse, reproduce, and change software or files. Watch these