Public Domain License
This is a “permissive” license that allows adopting the code into applications or projects and reusing the software as desired. That is in the public domain, anyone is free to use and modify the software without restrictions. Having said that, Public domain software may not always adhere to best coding practices. Furthermore, Code that doesn’t have an explicit license is NOT automatically in the public domain. A programmer or company that creates copyrighted software can choose to forego that copyright by donating the software to the public domain. Software in the public domain can be freely shared, modified, distributed, commercialized, and relicensed by the end user with essentially zero restrictions.
Literary works like the plays of William Shakespeare and famous novels like A Christmas Carol (Charles Dickins) or The Time Machine (H.G. Wells) are also part of the public domain. That means anyone is free to reprint, reproduce, recreate, or reinterpret these works, sell them, and make a profit.
The intellectual property associated with these works, as with open source software, belongs to the public.
GNU/LGPL – GNU Lesser General Public License (LGPL)
This license gives the rights to developers to link to open-source libraries within their own software. The resulting code can be licensed under any other type of license. The GNU Lesser General Public License (LGPL) was also created by the Free Software Foundation. This type of software license permits the end user to modify the program and incorporate the derivative version into a proprietary software product that can be licensed on their own terms and at their own discretion. This stands in contrast to the terms of the GPL software license types, which typically require creators of derivative works to give away the source code for free.
A permissive license is like a public domain license, but it may contain limited restrictions on how the end user may modify or distribute the software. The benefit of permissive licensing for software creators is that it allows them to retain their intellectual property and maintain some control over how their software is used while continuing to support open-source development and even licensing their product for free. There are several sub-types of permissive software licenses, each with its own specific terms and conditions for how the licensed software may be modified or redistributed.