ImageMagick and GD are 2 of the most frequently used graphic software libraries available. They make the dynamic creation and editing of images and graphs on a site feasible, so they should be present on a web server if you host your websites on it and you prefer to have something different than static images with fixed dimensions. If ImageMagick and GD are installed, you'll be able to edit any image in many ways - create thumbnails, change the colors, flip it, blur it, etc. Naturally, these tweaks are doable if the script application which you use on your internet site permits you to carry out such things. The 2 libraries can easily be used with numerous web development languages - PHP, Python, Perl, etc., and support more than one hundred commonly used image formats that you'll be able to work with - PNG, PSD, JPEG, TIFF, GIF and more.