Licensing works around copywrite's.. a GPL license as KDE-look prefers is a General Public Lisense which basically means that the image is in the public domain. People are free to distribute, edit, fix.etc.. the file you post as GPL. This is commonly known as Open Source software. If you are posting something that you did not orginally create it is common curtisy to give credit to the orginally author/artist/programmer of the file. See: http://www.gnu.org/philosophy/license-list.html for a complete explanation of GPL and the other licenses.