From PC World:
Photos and the Internet go together like peanut butter and jelly. For as long as there have been web browsers, people have generously posted photos online–which other people have then downloaded and used for their own purposes, whether or not they’ve actually asked for permission. To make it easier to legally and ethically reuse photos posted online, the Creative Commons license was created.
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Before we go any further, I should point out that every photo on the Internet has been taken and published by someone, and that means all of those images are implicitly under copyright. You don’t have to see an explicit copyright notice in order for an image to be protected by law. Indeed, all creative works are implicitly protected by U.S. copyright law.
Consequently, you shouldn’t save photos you find online and reuse them in your own work (such as on a website or in a blog post) without first getting permission from the copyright owner.
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Creative Commons is the name of a new way to make your work available to the Internet community. Of course, I say that Creative Commons is new, but that’s only true in comparison to our 200-year-old copyright law–Creative Commons was started in 2001by a nonprofit organization of the same name that has developed a number of licenses, all available for free, to help artists share their work.
In general, any Creative Commons license allows you to redistribute an image for noncommercial purposes, as long as you don’t modify the image. Dig a little deeper and you’ll discover there are a handful of conditions that can be attached to a Creative Commons license. The artist can choose to allow or prohibit commercial use of a work, allow it to be modified, or impose a “share alike” condition.
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If you choose to release your work under a Creative Commons license, that does not invalidate your copyright; it simply provides an easy-to-communicate license for distributing your work.
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The Internet is awash in photos with Creative Commons licenses, but there’s no question that the best place to look is Flickr, which makes it easy for people to license their photos as Creative Commons. When I need to finds a photo online for Digital Focus or any of my other blogging duties, I always head directly to Flickr’s search page and select both “Only search within Creative Commons-licensed content” and “Find content to use commercially.”
Link to the rest at PC World
Passive Guy posted this for a bit of copyright education. With text documents, it’s not difficult to use an excerpt from the larger work and fall under the Fair Use limitation on the exclusive rights of a copyright holder to control publication of a work.
One of the elements considered in determining whether a use of copyrighted material falls under Fair Use is the amount and substantiality of the portion of the copyrighted work used. 100 words excerpted from a 1,000 word work will look pretty good under the amount and substantiality test.
A photograph is a different matter, however, because most often the person using it will want to use the entire photo. You don’t want to show 20% of a photo of El Capitan and Half Dome in Yosemite, you want to show the entire mountain and its surroundings.

Randy Le'Moine Photography, Used Under Creative Commons License
In addition to Flickr, you can find a lot of photos and illustrations released under Creative Commons licenses on Wikimedia Commons and at CCFinder.
Wikimedia Commons will even provide html code to properly use a photo you find there. Hover your cursor over the following photo to see the license and attribution information Wikimedia automatically provided. This information accompanied the photo when it was uploaded to Wikimedia by the original photographer.
