Open source describes general practices in production and development which promote access to the end product's sources. It is regarded by some as a philosophy and by others a pragmatic methodology. Developers and producers had used many different phrases and jargon words before open source became widely adopted, as the early Internet years provided a rapid convergence of socially diverse production models. With the revolutionary increase in interactive communities and their direct involvement with the Internet, open-source software became the most prominent face of open source. Even though the Internet started in 1969 with open standards like RFCs, it wasn't until 1998 that open source became a label applied to software to denote the same collaborative effort which began the Internet. The open source model allows for the concurrent use of different agendas and approaches in production, and it contrasts with more isolated models.

History:

Open source software in the sense that the source code has been made publicly available has existed since the 1960s. However, in 1984 the Free Software Movement began its campaign for Free Software, meaning software that respects users' freedom and community, and explained that "free" in "free software" means "free as in free speech," and not "free as in free beer." But free software usually can be obtained at zero cost, so some misunderstood the aim of this movement to be "users should never pay," and perceived that as anti-commercial in spirit.

In 1998 the term "open source" was chosen in a strategy session held in reaction to Netscape's announcement of a source code release called Mozilla. The term was used to clarify the potential confusion caused by the ambiguity of the word "free" in the English language. This is often considered the birth of the open source movement and many consider the term to have been coined within the strategy session. None the less, many people claim that the birth of the Internet started the open source movement, while others consider open source to predate networks entirely, to the times when software was developed and passed about between academics freely. Later that year the Open Source Initiative formed and began using the term "open source" to describe software which follows its own criteria of openness, the Open Source Definition, which draws the lines differently from the criteria for "free software".

Also in 1998, critics attacked the term "open source" citing that it fosters an ambiguity of a different kind; that it confuses the mere availability of the source with the freedom to use, modify, and redistribute it.

The philosophy associated with the term "open source" emphasizes collaborative development, and thus it differs from the philosophy of "free software". Some who write about the community that includes both these philosophies' supporters use the terms Free and Open Source Software (FOSS) or Free/Libre/Open-Source Software (FLOSS), as a way to refer to this community and its software without taking a side between the two philosophies or their associated criteria.

(From Wikipedia)