By Mark L. Chambers

Today’s Apple iOS devices can all display or play the same media: photos, music, books, TV shows, and such. Heck, some iOS devices (such as your iPhone and iPod touch) can even share applications that you install. Therefore, it makes sense to effortlessly share all your digital media across these devices, and that’s what iCloud is all about. Apple calls this synchronization “pushing.”

Here’s a look at how the pushing process works. Imagine that you just completed a Pages document on your iMac (an invitation for your son’s birthday party), but you’re at the office, and you need to get the document to your family so that they can edit and print it using your son’s iPad.

Before iCloud, you had to attach the document to an e-mail message or upload it to some type of online storage (such as Dropbox or Microsoft SkyDrive), and then a family member had to download and save the document to the iPad before working with it. With iCloud, you simply save the document on your iMac to your iCloud Library, and OS X automatically pushes the document to the iPad! Your document appears on the iPad, ready to be opened, edited, and printed — and it appears on any other devices running iOS 5 or later (using the same Apple ID) as well. The following figure gives you an idea of what’s happening in the background when one of your devices pushes data using iCloud.

iCloud works by pushing data among all your iOS devices.

iCloud works by pushing data among all your iOS devices.

And iCloud isn’t limited to just digital media. Your iMac can also automatically synchronize your e-mail accounts, Calendar calendars and events, and Contacts entries with other iOS 5 or later devices across the Internet, so staying in touch is much easier no matter where you are, or which device you happen to be using at the moment.

Apple also throws in 5GB of free online storage that you can use for all sorts of things: not only digital media files but also documents that you’d like to save online for safekeeping. Items you buy through the iTunes Store — music, video, and applications — and the images in your Photo Stream do not count against your free 5GB limit. (More on how you can expand that 5GB limit later in the chapter.)

To join the iCloud revolution, you first need an Apple ID. If you didn’t create one during the initial Mavericks setup, you can create an Apple ID from the App Store.

You can also access your documents through the web at icloud.com. Log in with your Apple ID and password to send mail, access your contacts and calendar, edit your notes and reminders, locate your devices, and use online versions of Pages, Numbers, and Keynote. (Don’t forget that you can access those web-based, online iWork applications at any time, even when you’re using a PC!)