How Apple TV Works

It's only about 8 inches (20 centimeters) square, but Apple TV packs as much power as some computers. See more TV evolution pictures.
Courtesy of Apple

With its many incarnations of the iPod and other audio-related equipment, it may seem as though Apple has neglected the ubiquitous television in favor of entertainment products targeting music lovers. For an array of reasons, after its 2006 introduction, Apple TV fell off the radar of many casual digital video aficionados. Now, though, more and more people are buying Apple TVs as they discover the myriad ways they augment their HDTV experiences.

Apple began shipping the Apple TV in spring 2007, billing the product as a way to tie the power of your computer and high-speed Internet connection to the gorgeous display of an HDTV. More specifically, you need a TV with widescreen (16:9) enhanced-definition or high-definition capability and a High-Definition Multimedia Interface (HDMI), Digital Visual Interface (DVI) or component video input port.


Add an Ethernet network and iTunes store account to the mix, and you have everything you need to control and display photos, and play music and videos on your TV. You don't need a Mac-centric computer to make it work because Apple TV is compatible with PCs and Macs alike, and the media you use through the Apple TV isn't limited to the personal collection you're currently storing in your iTunes library. Apple TV also lets you leverage specific Internet tools to access a range of audio and video -- most notably HD-quality movies from major studios.

After reviewing feedback from the first round of Apple TV users in early 2008, "We learned what people wanted was movies, movies, movies," said Apple CEO Steve Jobs [source: Block]. Since then, Apple pushed to satisfy Apple TV devotees' desires for improved TV and movie options, a prime reason unit sales tripled in January 2009 compared to January 2008 [source: Apple Insider].

On the next few pages, you'll see how Apple TV works with your entertainment system and examine how a few software updates from Apple (as well as some inventive user modifications) contribute to Apple TV's newfound popularity.



Apple TV's Core

Apple TV and remote
Photo courtesy Apple

Apple TV's small, silvery case certainly doesn't look anything like a desktop computer, but its hardware list is very similar to a computer's. It features an Intel processor, 40GB or 160GB hard drive, 256MB of RAM, connectivity for both wired and wireless Ethernet networks, and an NVIDIA GeForce Go 7300 graphics card. HDMI and component jacks connect the device to your HDTV, and there's a USB port that's intended for technical service purposes. If your older standard definition TV has component jacks you can use the Apple TV, but unless it supports widescreen input the picture will be stretched and probably not much fun to watch. Although Apple could've provided letterbox formatting for standard definition TV, in keeping with company trends that focus on up and coming technologies, it opted to move on to the widescreen formats that will eventually dominate the TV marketplace.

Apple designed the Apple TV for its usability. Connect your TV to the Apple TV and it automatically detects your wireless network. Then you can synchronize the device to one computer's iTunes library and still access iTunes libraries on up to five other computers around your home. Hit the couch, grab your Apple TV remote control, and you can play music, watch popular TV programs, start a movie or stream content from YouTube, Flickr, or MobileMe.


You don't always need a network or even an Internet connection to use an Apple TV with your television, just as you don't need a computer to hear music on your iPod. You can simply synchronize it with the iTunes library on your computer and then play back files stored on your Apple TV's hard drive. The smaller 40GB version stores about 50 hours worth of video or 9,000 songs; the 160GB drive's capacity stores around 200 hours of video or 36,000 songs.

You can also use your Internet connection to browse Apple content online. Through the iTunes store, you can rent a newly released standard definition or HD movie with surround sound and begin watching in minutes. HD movies contain more data and take longer to transmit, so if you have a sluggish Internet connection you may have to wait longer for the movie to load. Apple indicates that wait times to start an HD-quality film range from less than 60 seconds (at 6Mbps [megabits per second]) or two hours if your speeds are closer to 2Mbps.

You have 30 days to start watching the movie and once you begin, you have to finish it within 24 hours. New releases, of course, cost a bit more than older flicks. You can also buy music or purchase TV shows a day after they air from the iTunes store.


Apple TV Software

Users can control Apple TV using a remote.
Photo courtesy Apple

As you can see, Apple TV functions as a traffic cop of sorts for your multimedia entertainment system. It enables a smooth flow of data from one device to another within a specific framework of rules that Apple designed.

Here's how the processes behind this system work.Let's imagine you want to play a new movie that you just downloaded to your iTunes library. The computer loaded with iTunes, your movie is in a second-floor home office and the Apple TV is connected to an HDTV in the basement entertainment room. A wireless router lets the Apple TV communicate with your office computer. To begin, you use the included remote control to interact with Apple TV menus displayed on your HDTV; you pick the movie option.


Your input goes to Apple TV's module controller software, which is the linchpin application that coordinates most of Apple TV's input/output capabilities. This application recognizes components as they are added or removed from your Apple TV network. What's more, it knows if you're using a regular infrared remote or the Remote application on an iPhone or iPod. In the latter case it recognizes that you need menus and icons formatted properly for your device's smaller screen.

Each component in your Apple TV network has its own subset of software that helps it communicate with the module controller. The module controller directs your request to the appropriate component in your network. In this case, it's your office computer, where the movie is cataloged in your iTunes library.

Your computer's software receives the movie request and forwards the movie data back to the module controller. The controller helps display a menu option on your HDTV that in turn lets you start the movie. Select Play and your computer begins streaming the movie through your wireless network to your TV, all thanks to the direction of the module controller.

In summary, the module controller software is the workhorse application that makes your Apple TV go. It keeps track of components connected to your local network, directs all of the vital commands you input, and controls each item that's displayed on the menus you see. And because data is filtered through Apple TV's software and processor, Apple can pick and choose the kind of file formats that work with Apple TV -- a key concept that irks some users, as you'll soon see.


Apple TV Compared to Other Media Devices

Apple TV works with a limited number of video formats. You can play clips encoded with the MPEG-4 (Moving Picture Experts Group) or H.264 video codecs at maximum resolutions of 720 x 432 pixels and 1280 x 720 pixels, respectively. This means you can play video from sources like the iTunes store and from YouTube, though in the latter case, those clips won't be true HD quality. You may notice that Apple TV doesn't support popular formats such as .AVI; you'll see later how limitations such as these caused many users to take matters into their own hands.

The Apple TV plays audio encoded with WAV, AAC, Apple Lossless or AIFF audio codecs. You can also use files encrypted with FairPlay Digital Rights Management technology, which is applied to all protected songs in the iTunes store. In addition, you can display photos saved as JPEG, BMP, TIFF, PNG and GIF image formats, meaning your HDTV will provide your treasured photos with a much larger stage than your digital camera's LCD or your computer screen.


For all of its capabilities, an Apple TV isn't an all-around media player. For instance, sans an optical drive, there's no way it will convince you to shelve your DVD player. And because Apple's business model encourages users to pay for TV and movie content, there's no DVR (digital video recorder) functionality.

You may wonder why you couldn't just mix and match similar hardware to create a setup that works like the Apple TV. The answer is that, well, you could, but it would be tough to assemble this collection of hardware for the price of an Apple TV. For instance, you could buy a Mac Mini, but that would cost more than an Apple TV and you'd have to deal with the overhead of buying a full-blown computer.

You could also just connect your computer directly to your TV, but only if you want to move your computer into the living room. If you own a laptop, you can connect it to your TV and play back your assortment of files. Your laptop will use a DVI connector, which won't look much different than video played through an HDMI connection. Like your desktop computer, though, your laptop isn't really a permanent part of an entertainment system.

You have other entertainment options at your disposal, too. Many people love the Roku, a media player that streams videos from Netflix, but that's the extent of this product's capabilities. The same goes for the direct-to-TV player offered by Blockbuster. A TiVo DVR will also let you stream Netflix to your TV, but you'll pay TiVo's monthly fee for these privileges.


Apple TV Controls

You choose Apple TV's entertainment options using a remote control to access onscreen menus.
Courtesy of Apple.

Apple TV features a graphical user interface based on a version of OS X 10 that Apple tailored specifically for Apple TV's capabilities. You use Apple TV's remote control to click through a series of menus and submenus displayed on your TV screen. These menus let you choose from audio and video content stored on the Apple TV itself or on any iTunes collections on your networked computers.

Soon after Steve Jobs introduced Apple TV, its software quickly became a target for critics who wanted more features and flexibility. For example, the Apple TV can't play Microsoft's copy-protected .WMA (Windows Media Audio) files from a Windows PC. Apple TV also doesn't let you find content from random Internet sources the way you can via a Web browser, instead forcing you to use YouTube, MobileMe or Flickr.


In February 2008, Apple addressed the complaints with a major software update called Take 2. This version and its subsequent releases let you substitute just about any third-party universal remote for the Apple TV remote, enabled volume control for audio playback, permitted a new range of playlist functions and added other capabilities. Most importantly, it enabled features that recent Apple TV buyers take for granted, such as the ability to rent movies from iTunes, purchase TV shows, view photos from MobileMe and Flickr galleries and play iTunes audio through the Apple TV and your stereo using AirTunes.

The included six-button remote lets you play and rewind or fast-forward through any video, or skip audio tracks, but remember that you don't have to use the remote that Apple gives you. Many universal remotes will work as well. For example, you can use a third-party remote to control your Apple TV, DVD player and television. Alternately, you can install the Remote application from iTunes to your iPhone or iPod Touch, both of which have keyboards that will come in handy for specific tasks, like typing keywords into the YouTube search engine.


Apple TV Hacks and Extended Functionality

Immediately after Apple TV's launch, users began hacking, or altering, its hardware and software to give the device new capabilities. Whether you're looking simply to stretch Apple TV's features a little or give it the ability to play content in new formats, there's a plethora of ways to tweak this product to your liking. A major caveat here: Although Apple can't stop you from hacking your Apple TV, doing so may void your warranty. You should also note that updates from Apple remove any hacked features you may install, but you can usually re-hack your Apple TV without difficulty.

Initial hacks targeted the first Apple TVs' 40GB hard drives, which wouldn't let you store many iTunes movies (around 1.5GB each) or TV shows (about 500MB each), without replacing them with more spacious drives. This procedure wasn't terribly complicated for advanced users but the physical changes did alter the product's aesthetics. This was only the opening act for Apple TV hackers, spawning sites such as AppleTV Hacks, where visitors trade tips for modifying their products.


Software hacks are easier for average users to perform and don't require you to poke around sensitive components with a screwdriver. A so-called patchstick process lets you download free software from the Internet to a USB flash drive, plug the drive into your Apple TV and then restart the Apple TV so that it boots using the software on the USB drive. Depending on the patchstick version you choose, your Apple TV will have upgraded features, including new codecs that play .AVI, .WMV and other popular video formats, or new networking capabilities.

Some hacks let you access a broad array of online content using XBMC and Boxee. The XBMC and Boxee modifications are popular because they let you play content in formats that Apple TV's original software won't, such as .AVI and .WMV video clips. You need to register for an account to use Boxee's popular combination of social interaction and multimedia content power. Once you do, you can use the software's interface that lets you share opinions on content with other visitors, stream Netflix videos, and more.

The downside to these hacks, from the standpoints of Apple and producers of copyrighted material, is that users can play just about any content they want, including pirated videos and audio. This is a blow not only to Apple's carefully constructed Apple TV business model, but it also steals profits from the makers of the material who are behind the purpose of owning an entertainment system to begin with.

To learn more about Apple TV and its capabilities, take a look at the links on the next page.


Lots More Information

Related HowStuffWorks Articles

More Great Links


  • Apple. "Apple TV Overview."
  • Apple. "Apple TV Specifications and Accessories."
  • Apple. "Apple TV Software Updates Details."
  • Apple. "Apple TV: Streaming Photos Via iTunes."
  • Biggs, John. "Boxee Makes Your Apple TV Better." Crunch Gear. October 1, 2008.
  • Block, Ryan. " iTunes and Apple TV Rentals and Purchases: What You Can (and Can't) Do." Engadget. January, 16, 2008.
  • Chen, Jason. "Apple TV 2.0 Review." Gizmodo. February 13, 2008.
  • Drawbaugh, Ben. "Apple TV hacked to enable USB." Engadget. March 30, 2007.
  • Graham, Bill. "Hacking the AppleTV: Get Your Boxee On." Apple TV Junkie. February 25, 2009.
  • Martin, David W. "Take Control of Your Apple TV With Your Universal Remote." Mac Life. November 11, 2008.
  • McLean, Prince. "What's Inside an Apple TV: Tear-down Reveals (Almost) All." Apple Insider. March 27, 2007.
  • McLean, Prince. "Apple TV Sales up Threefold, Will See Continued Investment." Apple Insider, January 21, 2009.
  • McNulty, Scott. "Apple TV 2.3: Now With More Remotes, and Remote Music." PC World. November 24, 2008.