 An assortment of previous and current iPod models. From back left to front right: fifth generation iPod classic, fourth generation iPod classic, iPod mini, second generation Product Red iPod nano, second generation iPod shuffle. | |
| Manufacturer | Apple Inc. |
|---|---|
| Type | Portable media player (PMP) |
| Units sold | Over 150 million worldwide as of March 2008[1] |
| Online services | iTunes Store |
iPod is a brand of portable media players designed and marketed by Apple Inc. and launched on October 23, 2001. As of 2008, the product line-up includes the hard drive-based iPod Classic, the touchscreen iPod Touch, the video-capable iPod Nano, the screenless iPod Shuffle and the iPhone. Former products include the compact iPod Mini and the spin-off iPod Photo (since reintegrated into the main iPod Classic line). iPod Classic models store media on an internal hard drive, while all other models use flash memory to enable their smaller size (the discontinued Mini used a Microdrive miniature hard drive). As with many other digital music players, iPods, excluding the iPod Touch, can also serve as external data storage devices. Storage capacity varies by model.
Apple's iTunes software can be used to transfer music to the devices from computers using certain versions of Apple Macintosh and Microsoft Windows operating systems.[2] For users who choose not to use Apple's software or whose computers cannot run iTunes software, several open source alternatives to iTunes are also available.[3] iTunes and its alternatives may also transfer photos, videos, games, contact information, e-mail settings, Web bookmarks, and calendars to iPod models supporting those features. Apple focused its development on the iPod line's unique user interface and its ease of use, rather than on technical capability. As of September 2007, more than 150 million iPods had been sold worldwide, making it the best-selling digital audio player series in history.[4]
Contents[hide] |
History and design
iPod came from Apple's "digital hub" category,[5] when the company began creating software for the growing market of personal digital devices. Digital cameras, camcorders and organizers had well-established mainstream markets, but the company found existing digital music players "big and clunky or small and useless" with user interfaces that were "unbelievably awful,"[5] so Apple decided to develop its own. As ordered by CEO Steve Jobs, Apple's hardware engineering chief Jon Rubinstein assembled a team of engineers to design the iPod line, including hardware engineers Tony Fadell and Michael Dhuey,[6] and design engineer Jonathan Ive.[5] The product was developed in less than one year and unveiled on 23 October 2001. Jobs announced it as a Mac-compatible product with a 5 GB hard drive that put "1,000 songs in your pocket."
Uncharacteristically, Apple did not develop the iPod software entirely in-house, instead using PortalPlayer's reference platform based on 2 ARM cores. The platform had rudimentary software running on a commercial microkernel embedded operating system. PortalPlayer had previously been working on an IBM-branded MP3 player with Bluetooth headphones.[5] Apple contracted another company, Pixo, to help design and implement the user interface under the direct supervision of Steve Jobs.[5] As development progressed, Apple continued to refine the software's look and feel. Starting with the iPod Mini, the Chicago font was replaced with Espy Sans. Later iPods switched fonts again to Podium Sans—a font similar to Apple's corporate font, Myriad. iPods with color displays then adopted some Mac OS X themes like Aqua progress bars, and brushed metal in the lock interface. In 2007, Apple modified the iPod interface again with the introduction of the sixth-generation iPod Classic and third-generation iPod Nano by changing the font to Helvetica and, in most cases, splitting the screen in half by displaying the menus on the left and album artwork, photos, or videos on the right (whichever was appropriate for the selected item).
In September 2007, during the course of a lawsuit with patent holding company Burst.com, Apple drew attention to a patent for a similar device that was developed in 1979. Kane Kramer patented the idea of a "plastic music box" in 1979, which he called the IXI.[7] He was unable to secure funding to renew the $120,000 worldwide patent, so it lapsed and Kramer never profited from his idea.[7] Kramer is now in talks with the company to discuss how he will be reimbursed.[7]
Trademark
The name iPod was proposed by Vinnie Chieco, a freelance copywriter, who (with others) was called by Apple to figure out how to introduce the new player to the public. After Chieco saw a prototype, he thought of the movie 2001: A Space Odyssey and the phrase "Open the pod bay door, Hal!", which refers to the white EVA Pods of the Discovery One spaceship.[5] Apple researched the trademark and found that it was already in use. Joseph N. Grasso of New Jersey had originally listed an "iPod" trademark with the U.S. Patent and Trademark Office in July 2000 for Internet kiosks. The first iPod kiosks had been demonstrated to the public in New Jersey in March 1998, and commercial use began in January 2000, but had apparently been discontinued by 2001. The trademark was registered by the USPTO in November 2003, and Grasso assigned it to Apple Computer, Inc. in 2005.[8]
Software
The iPod line can play several audio file formats including MP3, AAC/M4A, Protected AAC, AIFF, WAV, Audible audiobook, and Apple Lossless. The iPod Photo introduced the ability to display JPEG, BMP, GIF, TIFF, and PNG image file formats. Fifth and sixth generation iPod Classics, as well as third generation iPod Nanos, can additionally play MPEG-4 (H.264/MPEG-4 AVC) and QuickTime video formats, with restrictions on video dimensions, encoding techniques and data-rates.[9] Originally, iPod software only worked with Mac OS; iPod software for Microsoft Windows was launched with the second generation model.[10] Unlike most other media players, Apple does not support Microsoft's WMA audio format—but a converter for WMA files without Digital Rights Management (DRM) is provided with the Windows version of iTunes. MIDI files also cannot be played, but can be converted to audio files using the "Advanced" menu in iTunes. Alternative open-source audio formats, such as Ogg Vorbis and FLAC, are not supported without installing custom firmware onto an iPod (e.g. Rockbox).
During installation, an iPod is associated with one host computer. Each time an iPod connects to its host computer, iTunes can synchronize entire music libraries or music playlists either automatically or manually. Song ratings can be set on an iPod and synchronized later to the iTunes library, and vice versa. A user can access, play, and add music on a second computer if an iPod is set to manual and not automatic sync, but anything added or edited will be reversed upon connecting and syncing with the main computer and its library. If a user wishes to automatically sync music with another computer, an iPod's library will be entirely wiped and replaced with the other computer's library.
User interface
iPods with color displays use anti-aliased graphics and text, with sliding animations. All iPods (except shuffle and touch) have five buttons and the later generations have the buttons integrated into the click wheel—an innovation that gives an uncluttered, minimalist interface. The buttons perform basic functions such as play, next track, etc. Other operations such as scrolling through menu items and controlling the volume are performed by using the click wheel in a rotational manner. The iPod Shuffle does not have a click wheel and instead has five buttons positioned differently from the larger models. The iPod Touch uses no buttons for any of these functions, instead relying on a multi-touch input style similar to that of the iPhone.
iTunes Store
The iTunes Store is an online media store run by Apple and accessed via iTunes. It was introduced on 29 April 2003 and it sells individual songs, with typical prices being US $0.99, AU $1.69 (inc. GST), NZ $1.79 (inc. GST), €0.99 (inc. VAT), or £0.79 (inc. VAT) per song. Since no other portable player supports the DRM used, only iPods can play protected content from the iTunes Store. The store became the market leader soon after its launch[11] and Apple announced the sale of videos through the store on 12 October 2005. Full-length movies became available on 12 September 2006.[12]
Purchased audio files use the AAC format with added encryption. The encryption is based on the FairPlay DRM system. Up to five authorized computers and an unlimited number of iPods can play the files. Burning the files onto an audio CD, then re-compressing can create music files without the DRM, although this results in reduced quality. The DRM can also be removed using third-party software. However, in a deal with Apple, EMI began selling DRM-free, higher-quality songs on the iTunes Stores, in a category called "iTunes Plus." While individual songs were made available at a cost of US$1.29, 30¢ more than the cost of a regular DRM song, entire albums were available for the same price, US$9.99, as DRM encoded albums. On 17 October 2007, Apple lowered the cost of individual iTunes Plus songs to US$0.99 per song, the same as DRM encoded tracks.
iPods cannot play music files from competing music stores that use rival-DRM technologies like Microsoft's protected WMA or RealNetworks' Helix DRM. Example stores include Napster and MSN Music. RealNetworks claims that Apple is creating problems for itself[13] by using FairPlay to lock users into using the iTunes Store. Steve Jobs has stated that Apple makes little profit from song sales, although Apple uses the store to promote iPod sales.[14] However, iPods can also play music files from online stores that do not use DRM, such as eMusic or Amie Street.
Universal Music Group decided not to renew their contract with the iTunes Music Store on 3 July 2007. Universal will now supply iTunes in an 'at will' capacity.[15]
Apple debuted the iTunes Wi-Fi Music Store on 5 September 2007, in its Media Event entitled "The Beat Goes On..." This service allows users to access the Music Store from either an iPhone or an iPod Touch and download songs directly to the device that can be synced to the user's iTunes Library.
File storage and transfer
All iPods except for the iPod Touch can function in "disk mode" as a mass storage devices to store data files.[16] If an iPod is formatted on a Mac OS X computer it uses the HFS+ file system format, which allows it to serve as a boot disk for a Mac computer.[17] If it is formatted on Windows, the FAT32 format is used. With the advent of the Windows-compatible iPod, the default file system used on the iPod line switched from HFS+ to FAT32, although it can be reformatted to either filesystem (excluding the iPod shuffle which is strictly FAT32). Generally, if a new iPod (excluding the iPod Shuffle) is initially plugged into a computer running Windows, it will be formatted with FAT32, and if initially plugged into a Mac running Mac OS X it will be formatted with HFS+.
Unlike many other MP3 players, simply copying audio or video files to the drive with a typical file management application will not allow an iPod to properly access them. The user must use software that has been specifically designed to transfer media files to iPods, so that the files are playable and viewable. Aside from iTunes, several alternative third-party applications are available on a number of different platforms.
iTunes 7 and above can transfer purchased media of the iTunes Store from an iPod to a computer, provided that the DRM media is transferred to any of the five computers allowed for authorization with DRM media.
Media files are stored on an iPod in a hidden folder, together with a proprietary database file. The hidden content can be accessed on the host operating system by enabling hidden files to be shown. The audio can then be recovered manually by dragging the files or folders onto the iTunes Library or by using third-party software.
Hardware
| Chipset or electronic | Product(s) | Component(s) |
|---|---|---|
| Microcontroller | iPod (Classic) first to third generations | Two ARM 7TDMI-derived CPUs running at 90 MHz |
| iPod (Classic) fourth and fifth generations, iPod Mini, iPod Nano first generation | Variable-speed ARM 7TDMI CPUs, running at a peak of 80 MHz to save battery life | |
| iPod Nano second generation | Samsung System-On-Chip, based around an ARM processor.[18] | |
| iPod Shuffle first generation | SigmaTel STMP3550 chip that handles both the music decoding and the audio circuitry.[19] | |
| Audio chip | All iPods (except the shuffle and 6G) | audio codecs developed by Wolfson Microelectronics |
| Sixth generation iPods | Cirrus Logic audio codec chip | |
| Storage medium | iPod (Classic) first to sixth generation | 45.7 mm (1.8 in) hard drives (ATA-6, 4200 rpm with proprietary connectors) made by Toshiba |
| iPod Mini | 25.4 mm (1 in) Microdrive by Hitachi and Seagate | |
| iPod Nano | Flash memory from Samsung, Toshiba, and others | |
| iPod Shuffle and Touch | Flash memory | |
| Batteries | iPod (Classic) first and second generation, Nano, Shuffle | Internal lithium polymer batteries |
| iPod (Classic) third to sixth generation | Internal lithium-ion batteries |
Connectivity
Originally, a FireWire connection to the host computer was used to update songs or recharge the battery. The battery could also be charged with a power adapter that was included with the first four generations. The third generation began including a dock connector, allowing for FireWire or USB connectivity. This provided better compatibility with PCs, as most of them did not have FireWire ports at the time. The dock connector also brought opportunities to exchange data, sound and power with an iPod, which ultimately created a large market of accessories, manufactured by third parties such as Belkin and Griffin. The second generation iPod Shuffle uses a single 3.5 mm jack which acts as both a headphone jack and a data port for the dock.
Eventually Apple began shipping iPods with USB cables instead of FireWire, although the latter was available separately. As of the first generation iPod Nano and the fifth generation iPod Classic, Apple discontinued using FireWire for data transfer and made a full transition to USB 2.0 in an attempt to reduce cost and form factor. With these changes, FireWire could only be used for recharging.
iPod dock connector
Introduced in the third-generation iPod, a 30-pin dock connector allows iPods to be connected to a variety of accessories, which can range from televisions to speaker systems. Some peripherals utilize their own interface, while others use an iPod's own screen for access. Such accessories may be used for music, video, and photo playback. Because the dock connector is a proprietary interface, the implementation of the interface requires paying royalties to Apple.[20]
Accessories
Many accessories have been made for the iPod line. A large number are made by third party companies, although many, such as the late iPod Hi-Fi, are made by Apple. This market is sometimes described as the iPod ecosystem.[21] Some accessories add extra features that other music players have, such as sound recorders, FM radio tuners, wired remote controls, and audio/visual cables for TV connections. Other accessories offer unique features like the Nike+iPod pedometer and the iPod Camera Connector. Other notable accessories include external speakers, wireless remote controls, protective cases/films and wireless earphones.[22] Among the first accessory manufacturers were Griffin Technology, Belkin, JBL, Bose, Monster Cable, and SendStation.
The white earphones (or "earbuds") that ship with all iPods have become symbolic of the brand. Advertisements feature them prominently, often contrasting the white earphones (and cords) with people shown as dark silhouettes. The original earphones came with the first generation iPod. They were revised to be smaller after Apple received complaints of the earbuds being too large. The revised earphones were shipped with second through early fifth generation iPods, the iPod Mini, and the first generation Nanos. The earbuds were revised again in 2006, featuring an even smaller and more streamlined design. This third design was shipped with late fifth generation iPods and the second-generation nanos. All first generation iPod Shuffles and the second generation up until 30 January 2007 (when color models were introduced) were shipped with the second design; those that shipped after that date were destributed with the third design of the earbuds.
In 2005, New York's Metropolitan Transportation Authority placed advertisements on the subways warning passengers that "Earphones are a giveaway. Protect your device",[23] after iPod thefts on the subway rose from zero in 2004 to 50 in the first three months of 2005.[24]
BMW released the first iPod automobile interface,[25] allowing drivers of newer BMW vehicles to control an iPod using either the built-in steering wheel controls or the radio head-unit buttons. Apple announced in 2005 that similar systems would be available for other vehicle brands, including Mercedes-Benz,[26] Volvo,[27] Nissan, Toyota [28], Alfa Romeo, Ferrari,[29] Acura, Audi, Honda,[30] Renault, Infiniti[31] and Volkswagen.[32] Scion offers standard iPod connectivity on all their cars.
Some independent stereo manufacturers including JVC, Pioneer, Kenwood, Alpine, Sony, and Harman Kardon also have iPod-specific integration solutions. Alternative connection methods include adaptor kits (that use the cassette deck or the CD changer port), audio input jacks, and FM transmitters such as the iTrip—although personal FM transmitters are illegal in some countries. Many car manufacturers have added audio input jacks as standard.[33]
Beginning in mid-2007, four major airlines, United, Continental, Delta, and Emirates reached agreements to install iPod seat connections. The free service will allow passengers to power and charge an iPod, and view video and music libraries on individual seat-back displays.[34] Originally KLM and Air France were reported to be part of the deal with Apple, but they later released statements explaining that they were only contemplating the possibility of incorporating such systems.[35]
Audio performance
The third generation iPod had a weak bass response, as shown in audio tests.[36][37] The combination of the undersized DC-blocking capacitors and the typical low-impedance of most consumer headphones form a high-pass filter, which attenuates the low-frequency bass output. Similar capacitors were used in the fourth generation iPods.[38] The problem is reduced when using high-impedance headphones and is completely masked when driving high-impedance (line level) loads, such as an external headphone amplifier. The first generation iPod Shuffle uses a dual-transistor output stage,[36] rather than a single capacitor-coupled output, and does not exhibit reduced bass response for any load.
From the 5th generation iPod on, Apple introduced a user-configurable volume limit in response to concerns about hearing loss.[39] Users report that in the 6th generation iPod, the maximum volume output level is limited to 100dB in EU markets. Apple previously had to remove iPods from shelves in France.[40]
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