<quote http://aur.archlinux.org/guidelines.html>
Q: What is the difference between the AUR, COMMUNITY, and TUR? Why don't packages I upload to the AUR show up in pacman?
A: The TUR, or Trusted User Repository, was the old system used to manage user submissions. It had a number of flaws, so was discontinued. The TUR website is still up, but is dead and will be removed shortly. AUR is the official replacement for the TUR. It is a web system that allows users to submit their own PKGBUILDs for both the TUs and the general community to see. COMMUNITY is a new Arch repository, run by the TUs, that is available via pacman.
User submitted PKGBUILDs are available from the AUR, but because they have not been reviewed, packages are not available. If a PKGBUILD is reviewed, and receives many votes, it may "graduate" into the COMMUNITY repo. There it will easily be retrievable from pacman.
If you are a new user, it is safe to use the COMMUNITY repo, as packages have been verified. Any PKGBUILDs in the UNSUPPORTED section of the AUR have not been tested, and could be dangerous or broken. Use at your own risk.
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