Open Source
The fundamental principle of the Open Source Licensing is that it prohibits anyone from exclusively exploiting a given piece of work. In order to reflect this, a legal framework was originally developed to guarantee the openness by a certain set of principles. The principles as defined by the Free Software Foundation: the freedom to run the program, for any purpose (freedom 0); the freedom to study how the program works, and adapt it to your needs (freedom 1) -- access to the source code is a precondition for this; the freedom to redistribute copies so you can help your neighbour (freedom 2); the freedom to improve the program and release your improvements to the public, so that all members benefit (freedom 3) -- access to the source code is a precondition for this.