The CC BY-NC (Creative Commons Attribution-NonCommercial) license is one of the licenses offered by Creative Commons, an organization that provides free licenses for creators to use when sharing their work. This particular license allows others to remix, adapt, and build upon the licensed work, as long as it is for non-commercial purposes, and gives appropriate credit to the original creator.

Key aspects of the CC BY-NC license include:

1. Attribution: Users must give appropriate credit to the original creator, provide a link to the license, and indicate if changes were made. The credit should not suggest that the creator endorses the user or their use of the work.

2. Non-Commercial: Users may not use the material for commercial purposes. This means that they cannot sell the work or use it in any way that is primarily intended for or directed toward commercial advantage or monetary compensation.

3. Adaptation: Users are allowed to remix, transform, and build upon the material. The new creations must also be non-commercial, but they don’t have to be licensed under the same terms as the original work.

4. No Additional Restrictions: Users may not apply legal terms or technological measures that legally restrict others from doing anything the license permits.

This license is often used by creators who want to share their work freely but still retain some control over how it is used, particularly in ensuring that it is not used for commercial gain without permission.