CC BY License

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  • Share — copy and redistribute the material in any medium or format
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The licensor cannot revoke these freedoms as long as you follow the license terms.

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  • Attribution — You must give appropriate credit, provide a link to the license, and indicate if changes were made. You may do so in any reasonable manner, but not in any way that suggests the licensor endorses you or your use.
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A simple explanation of your rights

This section was reused from Tony Kuphaldt, “Lessons In Industrial Instrumentation”, Appendix B at:

This is an “open-source” textbook, which means the entirety of it is freely available for public perusal, reproduction, distribution, and even modification. All digital “source” files comprising this textbook reside at the following website:

The Creative Commons Attribution license grants you (the recipient), as well as anyone who might receive my work from you, the right to freely use it. This license also grants you (and others) the right to modify my work, so long as you properly credit my original authorship and declare these same rights (to my original work) for your own readers. My work is copyrighted under United States law, but this license grants everyone else in the world certain freedoms not customarily available under full copyright. This means no one needs to ask my permission, or pay any royalties to me, in order to read, copy, distribute, publish, or otherwise use this book.

If you choose to modify my work, you will have created what legal professionals refer to as a derivative work. The Creative Commons license broadly groups derivative works under the term adapted material. In simple terms, the fundamental restriction placed on you when you do this is you must properly credit me for the portions of your adaptation that are my original work. Otherwise, you may treat your adaptation the same way you would treat a completely original work of your own. This means you are legally permitted to enjoy full copyright protection for your adaptation, up to and including exclusive rights of reproduction and distribution. In other words, this license does not bind your derivative work under the same terms and conditions I used to release my original work,although it does require you notify your readers of this free source text and the License under which it is offered.

The practical upshot of this is you may modify my work and re-publish it as you would any other book, with the full legal right to demand royalties, restrict distributions, etc. This does not compromise the freedom of my original work, because that is still available to everyone under the terms and conditions of the Attribution license1. It does, however, protect the investment(s) you make in creating the adaptation by allowing you to release the adaptation under whatever terms you see fit (so long as those terms comply with current intellectual property laws, of course).

In summary, the following “legalese”2 is actually a very good thing for you, the reader of my book. It grants you permission to do so much more with this text than what you would be legally allowed to do with any other (traditionally copyrighted) book. It also opens the door to open collaborative development, so it might grow into something far better than what I alone could create.

1 You cannot pass my original work to anyone else under different terms or conditions than the Attribution license. That is called sublicensing, and the Attribution license forbids it. In fact, any re-distribution of my original work must come with a notice to the Attribution license, so anyone receiving the book through you knows their rights.

2“legalese” at