The Creative Commons’ new image search is online with over 300 million images

Creative Commons is a licence for creative works that allows the creator to offer different terms than what is possible under copyright. Most Creative Commons works are licensed Attribution-NonCommercial (CC BY-NC) or Attribution-NonCommercial-ShareAlike (CC BY-NC-SA). Attribution means you have to give the creator credit, noncommercial means the work can’t be used in a commercial setting, and sharealike means others can distribute the your modified work as long as they get the same rights that you had.

Yes, it can be confusing, but it does offer more rights than what is possible under regular copyright. Creative Commons has a page to describe what the different licenses mean.