One of the most important advocates of open source is a former programmer from MIT, Richard Stallman, who says that making software secret and preventing its dissemination is immoral, given the fact that it stops society from having access to value. More than that, this mean it also generates waste: because you cannot copy (and improve) the software, you have to rewrite it.

There are numerous mechanisms developed to protect software programs, and the majority of them are adapted from systems used to protect other creations of the human spirit, like patent, copyright or licence. In this paper there are presented the most important systems used to protect the intellectual property in software engineering and a comparison is done between the advantages of open source and closed source.