BSD licenses
lastmod 2018-08-17created 2015-10-223 edits
The BSD license is one kind of free software license. It is used by many programs, including BSD-family software.
The BSD license is so permissive that it can hardly be called a software license: anyone can modify the software and distribute the modifications without restriction. However, redistributing modified versions is not mandatory, so programs under the BSD license can also be used in commercial software that does not have to be made public.
This is the biggest difference from the GNU GPL, which requires derived software to carry the same license as the GPL. In other words, it ensures that source code is always distributed for derivative works as well, which reflects the will of Richard Stallman, who created the GPL. In the case of the BSD license, since BSD itself was created by a public institution, there is a strong sense of giving it back to the public, so the license itself lets anyone use it for their own purposes without any restriction; the GPL, on the other hand, can be said to reflect an intent to put the philosophy of free software into practice.