Mozilla, creator of the popular Firefox web browser, is one of the largest collaborative open source projects in the world. Working on Mozilla is challenging, fun, and one of the best ways to gain real-world [http://www.shindiristudio.com/ web design] and development experience. Getting involved with Mozilla means learning new skills, meeting new people, and having the opportunity to work on global software products with tens of millions of users. However, as exciting as it is, getting started can be intimidating and overwhelming—Mozilla has millions of lines of source code. This course will give you the knowledge you need to start building Firefox extensions by introducing you to the following topics (NOTE: a [[Topics in Mozilla Development|complete topic list]] is also available):