The Free Software concept, created by the researcher Richard Stallman, from MIT AI Lab, is based on the idea of a program and its source are scientific knowledge and, as the mathematical theorems, can not be hidden. The idea is that, if it is hidden, we could have few people controlling the knowledge - slowing, thus, the advancement of science.

In a general way, the principal difference between Proprietary Software and Free Software is in the fact that open source production is more efficient, cause once the source is released, people in all the world be interested and start to work on it. Besides increasing the development potential of a program, it stimulates the team job and reduces the costs.

Although we have the frivolous sensation that "free software" and "open source software" are the same stuff, there is one important difference between them: a free software is a program that has its source available for anyone who is interested on it, but each change has to be  published like another version of the original software. However, the open source software is available, without any restrictions about its changes.

It is important to highlight that computer programs (property or non-property) are protected by copyright legislation, and because of it, they have a patrimonial dimension. The owner of the program can donate or sell it and distribute it for free or for remuneration.
There are several open source products available in market. One of the most popular is the operating system Linux.

We can highlight between free softwares, and beyond the OS Linux, the office suites "Open Office" and the "KOffice"; the image editors as "Gimp" and "Gphoto"; the web browsers "Firefox", "Google Chrome" and "Konkeror"; the e-mail clients "Kmail", "Evolution" and "Thunderbird"; the database "MySQL", "PostgreSQL"; web servers like "Apache"; media players as "XMMS multimedia", "Noatum" and "KDE Media Player"; environment for managing Zope content; the integrating agent between Windows and Unix networks "Samba"; remote management with OpenSSH encryption and "Proxy server", "DNS server", "Open LDAP" and "LDAP server".

The obstacles free software have to face and overcome are not only to offer reliable, safe and robust solutions, that propitiate a nice perform, availability and cost savings. Solid monopolies must be overcome and, more than that, must work to a cultural change imposed by the large corporations.

However,according to an study realized with the hundred companies that invest more in information technology in Brazil, in 2004, Linux was adopted by 64% of them. What represents an increase of 12% compared to last survey. Large companies are using free software by reasons since hardware and software costs reduction until the facilities of update, modification and customization that systems offer.

The free software adoption enabled a cost saving of R$ 380 million to brazilian federal government by 2008. "It is a money that can be invested in another areas, in hospital constructions, schools, or can be invested hiring more employees to government and technological areas", said the coordinator of Serpro , Paulo Pastore.

Result of collaborative worldwide work, Brazil is not alone following this trend. Beyond countries as Germany, France, Spain and India, there is a growing number of companies adopting the new way making IT business, like IBM, Novell and HP.