GNU Lesser General Public License

The GNU LGPL is another very popular free and open source software licence. It is a weaker form of GPL. The main difference is with respect to the dynamic linking of shared libraries. LGPL allows proprietary software to dynamically link to shared libraries. Both FSF and OSI have approved the LGPL, making it a free and open source licence. LGPL is a copyleft licence. Both GPL and LGPL were created by the FSF itself. These two GPL family licences are used in almost half the software projects that were analysed by a company called Black Duck Software. This clearly shows the dominance of the GPL family of licences. LGPL is compatible with GPL and is mostly used to license libraries.