There is a lot of material on the web. Unfortunately, frequently its use is somehow restricted. Sometimes there is the unpleasant note “© all rights reserved”, but often there is no copyright information at all, which is not so different: you are not authorized to use the work.
For instance, if you go on the website of an university professor, you often find lecture notes and other educational work. You can assume that you can read and print them and use them for studying, but what else? Can you give them to a friend? What about adapting them for use in another course?
You can easily find images with search engines like Google Images, and they could be great tools if you have, say, to write an article, a leaflet, or the slides for a talk. Usually people pick images they like and use them without even thinking about copyright; but copyright exists, and it’s not always true that they can do it.
Most of the times the author will be glad to let you use his work, albeit not always. Maybe he would like to be cited in one way or another; maybe he would allow only certain kinds of use; maybe it’s OK to use it, but not to modify it. The point is that you cannot know, unless the author makes it clear. You can always write an email to him (if you know his email address), but you probably won’t. This is the reason why clearly stated licenses are so useful: they let you know exactly what you can do and what you can’t.
This is the greatest achievement of Creative Commons: Creative Commons are a set of modular, standardized, easily understandable licenses. Every Creative Commons license says: “at least to some extent, you can use my work, and you can give it to a friend, forever; but if you do give it to a friend, say him that I am the author”. There are six different licenses, depending on how the author answers to two questions:
- do you want to allow people to use you work also for commercial purposes?
- do you want to allow people to modify your work?
This is also one of the most important differences between Wikimedia Commons, the media archive of Wikimedia (used by Wikipedia and other projects), and many other archives (or the web in general): for each file are clearly stated the license and (usually) the author and the source.
If you do not know anything about these licenses, Creative Commons people have written real “human readable” (not “lawyer readable”!) of the licenses, like this one for Creative Commons by-sa.
They have also written a machine-readable version of their licenses: RDF codes that, embedded for instance in a web page, can make clear to a search engine or a browser under which license the work is released. This is implemented for instance in Google Image, where you can restrict to images under certain licenses.
I have not talked at all about why you should share you work; I hope it is clear to us all. My point is that you should make it explicit; you should ask yourself: “do I want to allow people to use my work? and how?”. And, in any case, you should clearly state how, and a Creative Commons license is the most effective way. And you should do it each time you put your work on the web.
(By the way, do you know that everything you write on Edgeryders is released under Creative Commons Attribution 3.0 Unported, isn’t it?)