Licenses for KDE Documentation

KDE uses the FDL (Free Documentation License) for all documentation. This license has several variants, some of which place restrictions on how content is used in other contexts.

The specific terms we use are:

Permission is granted to copy, distribute and/or modify this
document under the terms of the GNU Free Documentation License, Version 1.1
or any later version published by the Free Software Foundation; with no
Invariant Sections, with no Front-Cover Texts, and with no Back-Cover

This is the only version of the license that is safe to use for documentation that is to be distributed with KDE.

The items that may differ in other uses of the FDL are as follows:

with no Invariant Sections

Invariant sections are, as you might expect, sections that must not be altered in any reproduction of the content. The reasoning behind this, is so nobody can make a subjective claim, and attribute it to you, by altering your words.

For instance, if you say Foo is a terrible piece of software and the section is marked invariant, the developers of Foo can not take your writing, change it to say Foo is a great piece of software and still attribute that opinion to you.

For many people, this restriction is incompatible with the GPL and therefore some distributions choose not to include any user manuals that contain Invariant Sections. Since they must be reproduced verbatim, this also means we are not able to reuse such content in our own manuals, without including this statement.

For this reason, Invariant Sections are not permitted in documentation that is to be distributed with KDE, nor can we safely reuse content from other sources, if they include Invariant Sections.

It is not normally appropriate to write opinion pieces in KDE documentation. Such content should be restricted to your own website, or documentation that is not distributed with KDE, so the fact we outlaw Invariant Sections in KDE documentation is not normally a problem. If you think you have a special case, please raise it with the documentation team, and understand that including such sections may prevent some distributions adding your manual (or the software itself) to their distribution.

with Front-Cover Texts names of sections, with Back-Cover Texts names of sections

As with Invariant Sections, these are texts that may not be altered, and must be included in any reuse of any of the content. It also means we would have to alter our license to match that of the content we have reused. This leads to similar problems as that of the Invariant Sections.

This one mainly comes up if we want to use FDL content found from other sources (for instance, books or websites.) In these cases, the best approach is to ask the authors to permit relicensing, and offer to include their front/back cover texts anyway, but without having to change our license terms.


The terms of the FDL as used by KDE documentation, are entirely GPL compatible, and do not restrict the reuse of the content. Any deviation from these terms, or any change in license could restrict distribution of your software or documentation, and should only be undertaken with full knowledge of the consequences, and with written permission of all copyright holders.