ImageMagick is a collection of tools designed to view, modify, and manipulate images in nearly 70 different image formats. It also allows you to create images dynamically, making it suitable for Web applications.
ImageMagick is part of the Ports Collection.
ImageMagick will be installed to the ~/usr/local/ImageMagick/ directory on your server.
Although there are many ways to use ImageMagick, one popular use is to combine it with a script such as WebMagick to dynamically create thumbnails of images.
For more information about ImageMagick, see the ImageMagick Web site