These icons are under GPL license. To learn more about this kind of license, please read the 'gpl.txt' inside the file. Note about GPL license: this license talk about software (or part of the software), the icons are digital files, and they will be applied as a part of softwares, so the GPL can be applied to the icons. Why i'm using this kind of license? There's a lot of confusion about copyrights in digital graphic files (in theory, if a file don't have a 'registrant', the first that upload the file on Internet, is the (C) propietary), and sometimes appears 'rippers' becuase don't find any (C) where he/she downloads the file; the GPL license is inside the file, and it acts as a (C); obviously, the GPL give the oportunity to others to enhance and distribute different versions of my icons. Please, read the license.