Open-source software (OSS) often refers that computer software whose source code are allowed to study, improve and at times also to distribute the software under certain permissions. As we all know, Open source software is very often developed in a public, collaborative manner.

Open Source Definition was defined by Bruce Perens who is one of the founders of Debian. And this definition is used by the Open Source Initiative to determine whether or not a software license can be considered open source.

• 1.Free Redistribution
• 2.Source Code
• 3.Derived Works
• 4.Integrity of The Author's Source Code
• 5.No Discrimination Against Persons or Groups
• 6.No Discrimination Against Fields of Endeavor
• 7.Distribution of License
• 8.License Must Not Be Specific to a Product
• 9.License Must Not Restrict Other Software
• 10.License Must Be Technology-Neutral

Logo of Open Source Initiative

OSI is an organization dedicated to promoting open source software.It was founded in February 1998, by Bruce Perens and Eric S. Raymond, prompted by Netscape Communications Corporation publishing the source code for its flagship Netscape Communicator product.

Visit official site of Open Source Initiative

• Linux—— Operation System
• Eclipse—— programming software
• GNU Emacs—— text editor(actually I use it to write C programs)
• XFree86, X.Org
• Apache——HTTP server
• GNU GCC、Open64——Compiler
• Zope——office web application server
• Plone——Content Management System
• OpenOffice.org——office software
• Mozilla Firefox——Web Browser
• GIMP——Image processing software un GNU
• eMule——P2P software

List of open source software packages in Wikipedia