CC0 and the public domain

1. CC0 and the public domain

1.3 CC0 and the Public Domain
LOs: [1c]
Very open permission and no copyright at all are not the same thing. This distinction matters because people often treat all highly reusable works as if they were identical, but Creative Commons licenses, CC0, and the public domain operate in different ways.
As you saw in 1.2 The CC License Elements and the Six Licenses, every CC license combines permissions and conditions. Building on that idea, this subunit shows an important limit of the license system: CC0 is not one of the six CC licenses. Instead, it is a public-domain dedication, and that difference affects attribution and copyright status.
The source explains that CC0 or "CC Zero" allows a creator to waive all copyright and related rights to the fullest extent allowed by law. As a result, anyone may use the work for any purpose without asking permission or giving attribution. This differs from the CC licenses, which keep the creator's copyright in place and grant specific permissions under stated conditions.
The source also explains that works whose copyright has expired are in the public domain. This gives you a concrete comparison: a work can enter the public domain because copyright has expired, or a creator can dedicate a work to the public domain through CC0. In both cases, the result differs from even a very permissive license such as CC BY, because CC BY still requires attribution and still rests on the creator's retained copyright.
A clear real-world instance from the source is the direct contrast between CC0 and CC BY. The source notes that being very permissive is not the same as being public domain: CC BY still requires attribution because copyright remains with the creator, while CC0 does not. As you read, consider why that difference matters when you decide whether a work must be credited, requested, or simply reused.
Attribution
Title | Author | Source | License
CC0 1.0 Universal | Creative Commons | https://creativecommons.org/public-domain/cc0/ | CC BY 4.0

OUTPUT LICENSE: CC0 1.0