GD is a graphics library. It allows your code to quickly draw images
 complete with lines, arcs, text, multiple colours, cut and paste from
 other images, flood fills, and write out the result as a PNG file.
 This is particularly useful in World Wide Web applications, where PNG is
 one of the formats accepted for inline images by most browsers.
 .
 This is some simple command line tools and example code that use the GD
 graphics library.