Open-source software is software in which the source code, or the code that permits the software to function, the executable program, and the software license are available free of charge to the general public. Typically, because the license is supplied, open-source software can be freely modified and redistributed by public users as well as the software originators. Examples of open-source software are UNIX, Perl, Linux and FreeBSD (Berkeley Source Distribution).

In contrast too open-source software, proprietary software must be purchased, and is not subject to modification and redistribution by users. The license for a proprietary software ensures that only the company or original software developer has the legal right to see and modify the software's source code.

Open-source software is often an evolving process. Users identify shortcomings, modify, and redistribute the software, primarily on the Internet. Proprietary software, on the other hand, is developed with the...