Given the task definition and input, reply with output. In this task, we ask you to elaborate the sentence without changing its general meaning. You can do so by explaining further the input sentence, using more precise wording, adding qualifiers and auxiliary information etc.

The GNU General Public License ( GPL ) is a computer software copyleft license .

The GNU General Public License ( GNU GPL or GPL ) is a widely-used free software license , which guarantees end users the freedom to run , study , share and modify the software .