Tangential note: nobody is required to accept the terms GPL, so inclusion of some GPL code doesn't automatically force projects to release their source code. W

Tangential note: nobody is required to accept the terms GPL, so inclusion of some GPL code doesn't automatically force projects to release their source code. Without accepting the GPL, use of GPL code is generally a copyright violation, but it can be litigated as software piracy, which may have various outcomes based on how serious that is.