It is celebrated annually on the third Saturday of September Software Freedom Day. Its purpose is to familiarize a wide range of users with FLOSS/FOSS, which is open source software.

For the first time this day was celebrated on September 28 in 2004. Then the event gathered 70 teams. And next year, on September 10, more than 300 teams from 60 countries of the world took part. In 2006, it was decided to make the third Saturday of September the fixed date of the celebration.

Until this date, IT teams from all over the world are holding the following actions:

• Free distribution of FOSS discs.
• Presentations of personal computers with Free/Libre Open Source Software.
• Visiting schools and universities whose students use FOSS.
• Conducting open classes on patents, FOSS and other manifestations of free culture.

The main sponsor of the holiday in 2005 and 2006 was Canonical Ltd., which created the Linux Ubuntu operating system.