Developed by John Weidner, the Study Stack concept basically assists individuals to memorize information about various subjects, including geography, history, math, languages, and science. Users of the site can select one of the existing stacks, which consists of virtual study cards allowing individuals to learn at their own pace until they are satisfied with their progress. What is also particularly novel about this learning tool is that data entered for customized study stacks can be automatically displayed as a matching game, a word search puzzle, or a hangman game. So far, the site contains dozens of study stacks for each subject, with the areas dedicated to math and science containing quite a number of rather helpful stacks. With its wide range of applications, this site will be very helpful to students at different age levels and teachers who may be seeking to develop a new study tool for any number of topics or themes within a subject area.