Tham khảo tài liệu 'handbook phần cứng pu part 116', công nghệ thông tin, phần cứng phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | sells individual songs relatively easily and cheaply the typical rates being US EU or GB per song. iPods and specially licensed Motorola mobile phones are the only portable music players that can play the purchased music. The store became the market leader a few years after its launch rm caft w needed and Apple announced the sale of videos through the iTunes Store on 12 October 2005. Full-length movies became available from 12 September Purchased audio files use the AAC format with added encryption. The encryption is based on the controversial FairPlay digital rights management DRM system. Up to five authorized computers and an unlimited number of iPods can play the files. Burning the files onto an audio CD removes the DRM at a cost of reduced quality when re-compressed from one lossy format to another. iPods cannot play music files from other competing music stores such as Napster or MSN Music which use rival DRM technologies like Microsoft s protected WMA or RealNetworks Helix DRM. RealNetworks claims that Apple is creating problems for itself 131 by using FairPlay to lock users into using the iTunes Store. Steve Jobs has stated that Apple makes very little profit from song sales but Apple uses the store to promote iPod edit File storage All iPods can function as mass storage devices to store data files. If the iPod is formatted on a Mac OS X computer it uses the HFS Plus file system format. If it is formatted on Windows the FAT32 format is used because Windows cannot access HFS filesystems. The user must still use iTunes or a compatible third-party software to load audio videos and photos in such a way that they are playable and viewable on the iPod. Unlike most MP3 players simply copying files to the drive will not allow the iPod to properly access them however with the use of open-source software it is possible. An iPod formatted as HFS Plus is able to serve as a boot disk for a Mac computer allowing one to have a portable .
