The HTML headers list the JavaScript source files needed to run the application. Order matters here, as symbols must be defined before they are used.
The webgl
sources are provided by the Khronos Group, the standards body that defines WebGL. These sources include facilities that ease cross-browser compatibility and GL debugging.
The cuon
sources are provided by the authors of the WebGL textbook. These sources provide basic shader and matrix handling facilities that are required by WebGL applications but not built into WebGL itself.
Finally, prog.js
is the source of the application.