|Copyright||Reuse is not permitted. Permission from the owner must be requested.|
|Creative Commons||The material can be reused citing the author. Consult the different kinds of Creative Commons licenses and their characteristics.|
|Copyleft||The material can be reused citing the author.|
|Public Domain||The material can be used without restriction. On citing the resource, you must mention that it is from the public domain.|
|No license||It is not known whether reuse is permitted. You must request permission from the owner or seek another resource with a license that assures reuse is permitted. .|
When you look for any resource, you must consult the license to be sure that the resource can be reused and how it can be reused (for example, whether modifications are permitted). It is most advisable to search for resources filtering by licenses that permit their use, but if you have a resource you want to use and you found it somewhere else, you should consult the original source for the license it has.
We do not recommend searching for resources like images in Wikipedia or in Wikimedia, or in blogs or the like, either, because they tend not to be original sources and they might mistake the type of license. Always consult the original source.
Remember that to be sure of lawful use, you should search in the original source, not where third parties have reused it.
In the following example, we see that content from a web site cannot be reused without requesting permission. It is only permitted for personal use.