Max is a visual programming language for music and multimedia developed and maintained by San Francisco-based software company Cycling ’74. During its 20-year history, it has been used by composers, performers, software designers, researchers, and artists for creating recordings, performances, and installations. The Max program itself is modular, with most routines existing in the form of shared libraries. An API allows third-party development of new routines (called “external objects”). As a result, Max has a large user base of programmers not affiliated with Cycling ’74 who enhance the software with commercial and non-commercial extensions to the program. Because of its extensible design and graphical interface (which represents the program structure and the GUI as presented to the user simultaneously), Max has been described as the lingua franca for developing interactive music performance software.