is a portable media player marketed by Apple Inc. To date, there have been six generations of the iPod Classic, as well as a spin-off (the iPod Photo) that was later re-integrated into the main Classic line. All generations use a 1.8-inch hard drive for storage.
The "Classic" retronym was introduced with the introduction of the sixth-generation iPod Classic on 5 September 2007; prior to this, an iPod Classic was simply referred to as an iPod.
FIRST GENERATION October 23, 2001
Second generation In JULY 17, 2002
Third generation
April 28, 2003
Fourth generation July 19, 2004
Fifth generation October 12, 2005,
Sixth generation
September 5, 2007
The iPod's operating system is stored on its dedicated storage medium. An additional NOR flash ROM chip (either 1 MB or 512 KB) contains a bootloader program that tells the device to load its OS from the storage medium. Each iPod also has 32 MB of RAM, although the 60 and 80 GB fifth generation, and the sixth generation models have 64 MB. A portion of the RAM is used to hold the iPod OS loaded from firmware, but the majority of it serves to cache songs from the storage medium. For example, an iPod could spin its hard disk up once and copy approximately 30 MB of upcoming songs into RAM, thus saving power by not requiring the drive to spin up for each song. Rockbox and iPodLinux offer open-source alternatives to the standard firmware and operating system, respectively. However, at the current time these are both unavailable for use with the 6th generation iPod Classic due to encryption used on the official firmware.
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