The iTunes Store is a software-based online digital media store operated by Apple. Opening as the iTunes Music Store on April 28, 2003, with over 200,000 items to purchase, it is, as of April 2008, the number-one music vendor in the United States. On February 24, 2010, the store served its 10 billionth song download; this major milestone was reached in just under seven years of being online. iTunes accounts for 70% of worldwide online digital music sales, making the service the largest legal music retailer. While most downloaded files have previously included restrictions on their use, enforced by FairPlay, Apple’s implementation of digital rights management, iTunes initiated a shift into selling DRM-free music in most countries, marketed as iTunes Plus. On January 6, 2009, Apple announced that DRM had been removed from 80% of the entire music catalog in the U.S. Full iTunes Plus availability was achieved on April 7, 2009 in the U.S., coinciding with the introduction of a three-tiered pricing model, however TV shows and Movies are still FairPlay protected.

iTunes Store

iTunes Store 9.0.2 under Mac OS X 10.6 Snow Leopard
Opened	April 28, 2003 (as iTunes Music Store)
Pricing model	À la carte, tiered; limited time rentals available for some movies
Platforms	Mac OS X, Windows, Apple TV, and iOS.
Format	Protected AAC (.m4p) @ 128 kbit/s (no longer sold in the music store), audiobooks 32 and 64 kbit/s, Protected MPEG-4 Video (.m4v). As of April 2009, the iTunes Store sells unprotected AAC (.m4a) @ 256 kbit/s, and unprotected MPEG-4 Music Video (.m4v)(some still in protected format)
Restrictions	(Protected) Music Ã¢â‚¬â€ streaming to five computers every 24 hours, unlimited CDs (seven with an unchanged playlist), unlimited iPods and iPhones.
Catalogue	More than 14 million songs worldwide, 1,000,000+ podcasts (USA), 40,000+ music videos (USA), 3,000+ TV shows (USA), 20,000+ audiobooks (USA)2,500+ movies (USA), 300,000+ App Store Apps
Preview	90 seconds (Music, TV, & Video) / 90 seconds (Audiobooks) / 30+ seconds (Movies)
Streaming	Previews and Podcasts only
Protocol	iTunes Music Store Protocol (itms://)
Availability	See article
Features	Allowance, “Just For You”, Celebrity Playlists, gift certificates and gift cards, iMix, billboard charts, advanced search
Customer support	Web only; See article
Website	itunes.com