What does "All rights reserved" mean?

As a copyright owner, you might use the “All rights reserved” notice to indicate that you retain all rights provided by copyright law. As such, another person cannot reproduce, distribute and/or adapt any part of the work without your permission. Legal exceptions to this include private use and the right to quote from a work.

Legally, the notice is meaningless because a work is nowadays automatically protected by copyright. Yet many copyright owners still use it to emphasize their rights provided by copyright law.

If you want to be less strict and want to let others know directly that they can copy, publish and/or adapt your work and under which conditions, you can use a Creative Commons license. You can find more information on Licenses for open material.