The "Fair Use" doctrine of United States copyright law is a court doctrine which compromises between strict copyright protection (where you could not use anything from this site without consent) and some reasonable use without asking for consent. The four standards of Fair Use are generally said to be:
1. The nature of the copyrighted work must be creative and original enough to warrant copyright protection.
2. The purpose of the use of the copyrighted work should be for non-profit or educational purposes, as distinguished from being used for commercial gain.
3. The amount of material used from the copyrighted work should not be too large.
4. The effect of the use of the copyrighted work should not harm the potential market and value of the copyrighted work.
In short, so not use material from this site by copying large parts of it, and do not use material from this site for commercial use --- without asking us for permission.