Find relevant and reliable medical information on common disease from medical index.
The hardware of a computer is infrequently changed, in comparison with software and data, which are "soft" in the sense that they are readily created, modified or erased on the computer. Firmware is a special type of software that rarely, if ever, needs to be changed and so is stored on hardware devices such as read-only memory (ROM) where it is not readily changed (and is therefore "firm" rather than just "soft"). The iPod is a brand of portable media players designed and marketed by Apple Computer. Computer hardware is the physical part of a computer, including the digital circuitry, as distinguished from the computer software that executes within the hardware. The iPod is currently the world's best-selling digital audio player, and its worldwide mainstream adoption makes it one of the most popular consumer brands. All three models were released in 2005. It is in embedded systems in automobiles, microwave ovens, electrocardiograph machines, compact disc players, and other devices. Discontinued versions include two generations of the iPod mini and four generations of the full-sized iPod, all of which had monochrome screens (except for the iPod shuffle) and provide a simple user interface. As a music jukebox application, iTunes stores a comprehensive library of the user's music on their computer and can play, burn, and rip music