GNU General Publi License is free, copyleft license for software and other kinds of works.

You are free to share - to copy, distribute and transmit the work

to remix and adapt the work.

Under the condition that you attribute the work to the author in the manner specified.

Similar to Arribution with the addition that you may add your own attribution to amends made to the origional, so two or more attributions will be required.

Similar to Attribition with the exception of commercial and no amendments to the origional work are allowed, ie you may not alter, transform or build upon this work. This licence is not well suited to wordpress due to the very nature of wordpress .