“This is a copyleft license”
“Copyleft guarantees freedom of users”
/used:/
To describe a licensing” tool to ensure users’ freedoms
As a humorous subversion of the term “copyright” – where copyright limits users’ freedoms, copyleft promotes them
/recommendations:/
Use only to describe a specific kind of licenses (like GNU GPL or CC BY-SA)
Underline the values of copyleft mechanism