A PMP is a portable media player, which is capable to store media files like photos, music or movies and display and play them. One of the best PM players  from the market it is the iPod, a line of portable players designed and released by Apple Inc. at the end of 2001. It is available in many variations of models starting with the classic iPod, to the iPod Touch and the iPod Nano or the Shuffle iPod. It can be compared with the iPhone, the smart phone model launched by the same Company, but, in generally, experts consider it another type of product. The difference between the classic model and the others is that the files are stocked on a hard disk, while the flash memory card is the base for the upgraded products from the same line.
Using versions of Microsoft Windows operating system, iPods can download and use music from iTunes or some other software, like an alternative for this program. This dedicated program can   also transfer photos, games or contact information. Thanks to the Lotus upgrade, a program released in collaboration with IBM, iPods can be used also for e-mails and calendars.
From September 9, 2009, iPod had been sold all over the world and become the best selling media digital player from all the times.
The iPod can play a lot of audio formats like the classical MP3 to the  M4A, WAV or AIFF or AAC. The Apple Inc. introduced with the iPod Photo the possibility to display JPEG, PNG, TIFF and, of course, the BMP format. Starting with the fifth generation, iPod was able to play also the MPEG-4 format, which defines a system of compressed audio and video data.
The first model used the Mac OS software but, starting with the second generation, they implemented the Microsoft Windows. Yet, iPods don't support the WMA files, but there are some converter programs special made for this format. Also, they cannot play the MIDI format, so popular this days, but it is able to replay the alternatives for it, like FLAC or Ogg.
The iPod have an easy interface, intuitive, for all categories of people that are targeted. With slide graphics and anti-aliased text, have an attractive look and design. All models, except the one with touch screen possibilities, have five integrated buttons, representing the basic functions as menu, play, stop, next or previous. Some models have this functions integrated in the click wheel button. Its design reminds of the cool and popular current named minimalism, because of it's curves, simply lines and shine material. The iPod Shuffle don't have integrated any buttons for control on the player but the user can do the specifically functions using a small button attached to the head phone set. Also, near the next/ previous, stop/ play buttons it contains also a volume button.
Because it is designed to keep you busy while you have some free time or to make you enjoy every moment, near opportunity to play music and movies, iPod offers you also the possibility to play games like the well- known Brick or Cubis 2. The 5th generation added to the game collection some new games like Mahjong, Pac Man, Tetris, Zuma, Vortex or Texas Hold Em'. The format used for this games it is  .ipg, a disguised type of the .zip archives.
You can compare the iPod with a mass portable storage for  data files and can be used as a boot disk for a personal computer. It can be formatted using the FAT32 in Windows, but, this procedure will take place every time a new iPod it is plugged to a computer using a Windows operating system. If the computer it is using a Mac OS X it will be formatting using a HFS+.
This device it is using a special software for transferring data and a simple copy/ paste, like the most other mp3 players, it will involve bad functionality, iPod can't play this type of files. You can use the iTunes software for this process, but there are some other developed programs available on the internet.
Using a database file, media data is stored on iPod in a hidden folder, unable to be seen in normal mode.
The configuration for this devices it is an optical one for a long and standard life. It have a microcontroller chip made by SigmaTel   which is able to handle the  music decoding and the audio circuitry. Wolfson Microelectronics contributed with the audio chip and  the storage flash memory it is from Samsung, a leader for the market in this domain. It have internal batteries made from lithium and a 3.5 inch display available for the iPod Touch or a 2.5 inch available for other versions.
A large numbers of accessories can be found on the market, specially for the iPod lines, like FM tuners, Â sound recorders, audio/ visual cables so the user to be able to connect it to a TV, remote controls. They even released an iPod Camera Connector and some external speakers.
