iTunes Match is a subscription service from Apple that enables users to sync and share their music catalogs with all of their devices that have iTunes accounts. The $24.99/year iTunes Match service utilizes Apple's iCloud for syncing a user's music catalog and iTunes for managing the libraries, purchasing and downloading music, and playing content.
iTunes Match can be accessed directly from iTunes on desktops and laptops, and from the Music app on iOS devices. The iTunes Match service stores music purchased through the Apple App Store, music imported from CDs and music purchased through services other than iTunes. iTunes Match subscribers are also able to listen to iTunes Radio stations free of advertisements.