OpenLP, its dependencies, and any plugins need to be correctly licensed in order to allow people to use and redistribute the software. Below is a list of popular licenses that are used by many open source projects around the world, with a brief description of the license and a link to the full text of the license.
| License | Description | Link |
|---|---|---|
| GNU General Public License | The GNU General Public License (GPL) is one of the most popular and oldest of the open source licenses. The GPL ensures the preservation of the four software freedoms. OpenLP uses this license. | Full text |
| GNU Lesser General Public License | The GNU Lesser General Public License (LGPL) is another popular open source license. It differs from the GPL by allowing proprietary software to use it without the license being applied to the proprietary software too. | Full text |
| Apache License | The Apache License is a popular open source license used by many well known open source projects. It originated from the Apache web server and the Apache Software Foundation. | Full text |
| BSD License (3 clause) | The BSD License is part of a group of permissive open source licenses. The 3-clause version of the license is a revision of the original 4-clause version, which simply requires all code to retain the license. | Full text |
| MIT License | The MIT License (LGPL) is another permissive open source license. It originates from the Massachusetts Institute of Technology in the late 80s. | Full text |
| Mozilla Public License | The Mozilla Public License (LGPL) is what is known as a weak copyleft license. It is used by all the Mozilla Foundation software projects, including Firefox and Thunderbird. | Full text |