To a certain extent, every type of file on your PC could be considered a media file. However, most users associate audio, picture, and video files as Media Files. Every media file has an extension, that the computer uses to associate with a program. Extensions are listed after the file name (for example this textbook has the file name “Computer Fundamentals for Technical Students Textbook” and the file extension is.” pdf” for portable document format. Depending on your Windows View settings, extensions may be hidden by default as changing a file extension could create errors in your computer. You can change viewing properties by launching a Windows Explorer Window, clicking on the “View” tab, and making sure “File Names and Extensions” is checked. In addition, users may also right-click on the file, then navigate to file properties, and view the type of file. Users may also change the program associated with that extension by clicking on the “Change” button next to the “Opens with” section of the screen.