mid - This extension indicates a sound file created with a Musical Instrument Digital Interface. Windows Media Player will open and run these files, however they don't sound like normal .wav or .mp3 files (described later). .Mid files are designed to product synthetic sounds using a computer's sound card. " A dirty fan doesn't rotate fast enough to keep that motor cool and a completely clogged fan just stops rotating altogether. This causes the computer's motor to work harder - and a harder working motor can raise the electric bill! Worst case scenario: the motor can overheat and stop working as well. If you're familiar with MS-DOS at all, you'll recall that it's a command-driven operating system that performs functions issued at the C:> prompt. The only way to get an MS-DOS computer to do something was to type a command at this prompt and if you can imagine, it was a rather cumbersome way to use a computer. The keyboard and mouse controls give users the option of speeding up or slowing down the movements of both of these peripherals. For those entering the United States from a foreign country, users will appreciate how Windows grants use of keyboard layouts native to their original language. Other uses will appreciate the different selection of cursors and the ability to add additional ones. Orphans are usually files that contain temporary data created by a program, files created by the user, partial files left over from a computer crash, or any other kind of miscellaneous files created for almost any other reason. The problem is that an uninstall program doesn't delete the orphan files it leaves behind because they were never part of the program when it was first installed. It can kill motivation, desire, and a true willingness to create a good product. In a commercial setting, participants work for a paycheck rather than for the product. And this is what puts open source projects far ahead of its monetized competition. As a software user, this means you can contribute to an open source project as well, and help to develop it into a product that reflects your direct preferences.