ImageMagick and GD are 2 of the most popular graphic software libraries on the market. They make the dynamic creation and editing of images and graphs on an internet site feasible, so they ought to be set up on a web server if you host your sites on it and you would like to have something different from static images with fixed dimensions. If ImageMagick and GD are present, you shall be able to edit any image in various ways - create thumbnails, change the colors, flip it, blur it, etc. Of course, these adjustments are possible if the script app that you employ on your website allows you to do such things. The 2 libraries can be used with a lot of web development languages - PHP, Python, Perl, etcetera., and support more than 100 commonly used image formats which you will be able to work with - PNG, PSD, JPEG, TIFF, GIF and others.