The iPod is a brand of portable media players designed and marketed by Apple Computer. Devices in the iPod family are designed around a central scroll wheel (except for the iPod shuffle, which uses click buttons) and the full- sized model stores media on an internal hard drive, while the smaller iPod nano and iPod shuffle use flash memory. Like many digital audio players, iPods can also serve as external data storage devices. Apple chose to focus its development on the iPod's simple user interface and its ease of use, rather than on technical capability. As of 2006, the lineup consists of the 5 th generation iPod that plays videos; the smaller, second generation iPod nano; and the display-less iPod shuffle. These models were updated in 2006. The bundled software used for transferring music, photos and videos is called iTunes. As a jukebox application, iTunes stores a comprehensive library of music on the user's computer and can play, burn, and rip music from a CD. The most recent versions have photo and video synchronization features. These features open up the possibility of playing back standard definition quality television and movies from the iPod onto a television set. In addition to the iTunes Store others sources of legal television content prepared for iPods include Google Video. Many of these services work only in the US, including iTunes. 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. Some of Apple's design choices and proprietary actions have, however, led to criticism and legal battles. Contents [hide] 1 History and design 2 User interface 3 Software o 3.1 iTunes Store o 3.2 File storage o 3.3 Additional features o 3.4 Open-source alternatives 4 Connectivity 5 Chipsets and electronics 6 iPod models o 6.1 Special edition and color variants 7 Criticisms o 7.1 Battery life advertising o 7.2 Non-replaceable batteries o 7.3 Bass response o 7.4 Equalizer o 7.5 Worker exploitation 8 Patent disputes 9 Sales 10 Advertising o 10.1 Earphones 11 Accessories o 11.1 Car integration 12 See also 13 References 14 External links [edit] History and design The iPod came from Apple's digital hub strategy, as the company began creating software for the growing market of digital devices purchased by consumers. While digital cameras, camcorders and organizers had well- established mainstream markets, the company found digital music players lacking in user interface and decided to develop its own. Hardware design of the 3 rd generation iPod. Tony Fadell, a former Philips executive in the company's Windows CE division, left Philips to create a hard drive based MP3 player and a music service [1] . He founded a company, Fuse, to develop and sell the idea to major media companies. After RealNetworks turned him down, Apple accepted and they began developing the iPod in February 2001, one month after iTunes was released. It was announced to the public on 23 October 2001 as a Mac- compatible product with a 5 GB hard drive that put "1000 songs in your pocket." Uncharacteristically, Apple decided not to develop the iPod's software in- house. Instead, Apple used a Design Chain and contracted with PortalPlayer, who already had a reference design (based on 2 ARM cores) with rudimentary software running on top of a commercial microkernel embedded operating system. PortalPlayer had been working on an IBM-branded MP3 player with Bluetooth headphones. [1] Apple contracted another company, Pixo, to create and refine the user interface, under the direct supervision of CEO Steve Jobs. Once established, Apple continued to refine the look-and-feel. Starting with the iPod mini, the Chicago font (once used on early Macintosh computers) was replaced with Espy Sans, which was originally used in eWorld and Copland. The most recent iPods have switched fonts again to Myriad – Apple's new corporate font. The iPods with color displays adopted some Mac OS X themes like Aqua progress bars and brushed metal in the FM tuner and lock interfaces. [edit] User interface The display screen of a 5 th generation iPod, playing the song Feel Good Inc. by the band Gorillaz The iPods with displays use high quality anti-aliased graphics and text, with sliding animation. These iPods have five buttons and newer generations have the buttons integrated underneath the scroll wheel, an innovation which confers an uncluttered, minimalistic interface. The buttons are: Menu — to traverse backwards through the menus, and toggle the backlight on older iPods Center — to select a menu item Play / Pause — this doubles as an off switch when held Fast Forward / Skip Forward Fast Reverse / Skip Backwards The other operations such as scrolling through menu items and controlling the volume are handled by the scroll wheel in a rotational manner. A Hold switch on the top of the unit prevents accidental button presses. The iPod shuffle has five buttons that function differently to the larger models. It has a Play / Pause button in the center, surrounded by four buttons: Volume Up / Down and Skip Forward / Backwards. Newer iPods automatically pause playback when the headphones are unplugged from the headphone jack, but playback does not resume when the headphones are re-inserted. An iPod that has crashed or frozen can be reset by switching 'Hold' on and off, and then holding Menu and Center (Menu and Play on the 3G iPod) for 6 seconds. [edit] Software It has been suggested that IPod Video Restrictions be merged into this article or section. (Discuss) The iPod can play MP3, M4A/AAC, Protected AAC, AIFF, WAV, Audible audiobook, and Apple Lossless audio file formats. The 5 th generation iPod can also play MPEG-4 (H.264/MPEG-4 AVC), .mp4 and QuickTime video file formats, with restrictions on video dimensions, encoding techniques and bitrates. Apple does not support Microsoft's WMA audio format – unlike many other media players – but a converter for non-DRM WMA files is provided with the Windows version of iTunes. MIDI files cannot be played, but can be converted to audio files using the "Advanced" menu on iTunes. Alternative open-source audio formats, such as Ogg Vorbis and FLAC, are not supported, possibly because they were not developed by media standards bodies (such as the MPEG group) of which Apple is a member. Each time an iPod connects to its host computer, iTunes can synchronize music playlists or entire music libraries and the user can choose for automatic or manual synchronization. Song ratings can be set on the iPod and synchronized later with the iTunes library. [edit] iTunes Store Main articles: iTunes and iTunes Store The iTunes Store (formerly iTunes Music Store) is an online media store run by Apple and accessed via iTunes. It was introduced on 28 April 2003 and it . month after iTunes was released. It was announced to the public on 23 October 2001 as a Mac- compatible product with a 5 GB hard drive that put "1000 songs in your pocket." Uncharacteristically,. As a jukebox application, iTunes stores a comprehensive library of music on the user's computer and can play, burn, and rip music from a CD. The most recent versions have photo and video. best-selling digital audio player and its worldwide mainstream adoption makes it one of the most popular consumer brands. Some of Apple's design choices and proprietary actions have, however,