The PatchWork Graphical Language (PWGL) is a visual programming that is a free Lisp-based cross-platform which can be used for computer-aided composition, music analysis, and sound synthesis. PWGL is a programmed ANSI Common Lisp that is compatible to source-code across several different operating systems that includes Macintosh OS X, Microsoft Windows, and Linux. PWGL has the ability to integrate several programming paradigms which include functional, object-oriented, and constrained-based one with high-level visual representation of data while also having the capability of solving a wide range of musical problems. A comparison between PWGL and two other Lisp-based composition environments has been made while the text-based and visual programming in general have also been compared to determine how PWGL is positioned within these categories. The main visual components of the system is then presented while the primary principles which allow users to manipulate a visual patch while the programming interface allows the extension of the system with user libraries, boxes, and menus. Finally, a short survey of the PWGL Tutorial concept has been given that can be used for demonstrations, pedagogical purposes and even for private study.