Software Freedom Day is an annual worldwide celebration of free open source software (FOSS) that takes place every third Saturday of September. It is celebrated around the general objective of promoting the benefits of using high-quality FOSS education, in government, at home, and in business — in short, everywhere!
The first celebration of Software Freedom Day took place in 2004 with twelve teams participating. At its peak in 2011, more than 400 events were organized by FOSS advocates in over 100 cities worldwide. – SFD PHL