When a friend sends you an e-mail with an attachment that contains a file extension, Dot What? removes the mystery of what to do with the file. Type in the file extension, and Dot What? reveals its description, recommended application to for opening it and even a corresponding Web site. Dot What? contains a database with more than 1500 Mac, PC and UNIX file extensions, a description of file type, the recommended application to open the file with and a Web address. A reference guide is also included. For more detailed information, including on updates, please read the documentation or visit the home page.