Introduction

Abstract

Since the formulation of its historic roots in Richard Stallman’s (1999) revolutionary ideas about software freedom in 1984 and its actual inception in 1998 open source software (OSS) has come a long way, evolving into a major social and economic phenomenon. For example, the infrastructure of the internet is largely based on OSS programs such as Apache HTTP Server or sendmail and on the consumer side 25% of all internet users surf the web with the OSS browser Firefox (Net Applications 2010). Commercially, Fauscette (2009) estimates the revenues generated with OSS products in 2008 at nearly $3 billion. Finally, the development platform SourceForge.net (2010) hosted the impressive number of over 225,000 OSS projects in April 2010.