It also includes Photo Stream, which wirelessly pushes photos you take with your iPhone, iPad, or iPod touch to the Pictures library on your PC --- no cable syncing required.
You can also share select photos with friends and family using Shared Photo Streams, complete with notifications and comments.
Note: To create an iCloud account you need an iPhone, iPad, or iPod touch with iOS 5 or later, or a Mac with OS X Lion v10.7.2 or later. Microsoft Outlook 2007, 2010 or an up-to-date browser is required for accessing email, contacts, and calendars.
iTunes in the Cloud
You never know when you'll suddenly be in the mood to listen to a favorite song, rewatch a classic movie, or laugh at that hilarious sitcom episode with a friend. With iCloud, you can have iTunes automatically download new music purchases to all your devices the moment you tap Buy. You can also access past music, movie, and TV show purchases from any of your devices --- wirelessly and without syncing.1 And whenever you play a movie, TV episode, podcast, iTunes U lesson, or audiobook on one device, all your other devices will automatically remember where you left off. Just sign in to the iTunes Store with your Apple ID.
With iTunes in the Cloud, the music you buy from the iTunes Store automatically appears on all your devices.1 And for music you haven't purchased from iTunes, iTunes Match is the perfect solution. iTunes Match is built right into iTunes on your computer and the Music app on your iOS devices.2 It lets you store your entire collection in iCloud, even music you've imported from CDs or purchased somewhere other than iTunes. When it's in iCloud, it's available on all your devices. So you can enjoy all your music anywhere, anytime --- on your iPhone, iPad, iPod touch, Mac, PC, or Apple TV.
With Photo Stream, you can take a photo on one iOS device and it automatically appears on all your other devices, including your Mac or PC. Import new pictures to your computer from a digital camera, and iCloud sends copies over Wi‑Fi to your iPhone, iPad, and iPod touch. You can even view recent photos on your big-screen TV via Apple TV. There's no syncing, no email attachments, no file transfers. Your pictures are just there --- on whichever device you happen to have handy.
Documents in the Cloud
You can create amazing documents and presentations on your Mac, iPhone, iPad, and iPod touch. And with iCloud, you can keep that work up to date across your Mac and all your iOS devices. You don't have to manage your documents in a complicated file system or remember to save them to a special folder. Your documents --- with all the latest edits --- are stored in your apps, so they automatically appear everywhere. iCloud is already built into apps like Keynote, Pages, and Numbers. It also works with other iCloud-enabled apps. So you can do things like create a to-do list on your Mac and make edits to it on your iPhone. Start sketching on your iPod touch and add the finishing touches on your iPad. Or start a game on your iPad and pick it up at the same level on your iPod touch.
Calendar, Contacts, and Mail
iCloud stores all the stuff you can't live without --- your calendars, contacts, and email --- and keeps it up to date across all your devices. Say you delete an email, add a calendar event, or update a contact. iCloud makes all your changes everywhere. Same with your notes, reminders, and bookmarks.
If you own multiple iOS devices, iCloud makes sure your apps are everywhere you want them. Download a new app on your iPhone, and it automatically appears on your iPad. You don't have to worry about keeping your devices in sync because iCloud does it for you. Or say there's an app you bought way back when that you wish you had on your new iPod touch. iCloud lets you see your past downloads in one convenient place: your purchase history on the App Store. Since you've already purchased these apps, you can download them again --- at no additional charge --- to your iPhone, iPad, or iPod touch.
With iCloud, the best place to read is anywhere you have an iOS device. As soon as you buy a new book from the iBookstore, iCloud automatically pushes it to all your other devices. Start reading on your iPad, highlight some text, take notes, or leave a bookmark, and iCloud automatically updates your iPhone and iPod touch, too. Once you buy a book, it appears in the iBooks library on all your iOS devices. Which means you can download any of your purchased titles anytime you want. And it won't cost you anything extra.