Photo courtesy Apple iTunes is the most popular jukebox software in the world. See more iTunes pictures.

Remember when Microsoft was the bad guy and Apple was the underdog? Funny how a brilliant idea can change everything. With the raging success of the iPod and its powerhouse sidekick, iTunes (or is it the other way around?), you'll now find almost as many people ranting about Steve Jobs as about Bill Gates. Where one person sees the coolest duo to hit electronics since TiVo met the TV, another sees plans for world domination. And it's all about one word: proprietary.

In this article, we'll see what makes iTunes the most popular jukebox software in the world, review some its more advanced functions, explore the integrated Music Store and find out why the whole setup is inspiring some lawsuits and epic hacking wars. First, let's cover the basics.

iTunes is a piece of software that lets you add to, organize and play your digital media collection on your computer, as well as sync it to a portable device. It's a jukebox player along the lines of MusicMatch and Windows Media Player, and you can use it on a Mac or Windows machine. The most significant difference between iTunes and some other media players is the built-in iTunes Music Store (where you can get podcasts, music videos, movies, audiobooks and TV shows, too) and its multi-level integration with Apple's iPod portable media player.

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But a portable media player isn't the only way to listen to music through iTunes. There's your Mac OS X or Windows 2000/XP computer, first off -- if you've got a sound card and a set of speakers (and you probably do), that's all you need to use iTunes. You can also use your iTunes library with one of the Motorola/Cingular iTunes phones, which let you download up to 100 songs to the phone. Apple's wireless-networking hub, AirPort Express, is now "AirPort Express with AirTunes" -- you can wirelessly stream iTunes music from your computer to your hub-connected home-theater speakers. With this setup, you control playback via your computer. With another iTunes stream receiver, Roku's SoundBridge Network Music Player, you control everything through the SoundBridge remote control. So you're not limited to any single option when it comes to playback. But you are limited in some other ways.

Photo courtesy Apple iPod video

iTunes compatibility in the realm of portable players is a bit of a quagmire, which is part of the reason why some people just avoid iTunes entirely. You can use the iTunes Mac software with, say, a Creative Nomad MP3 player (see iTunes for Mac OS X: Compatible Players for a complete list). But iTunes for Windows only supports the iPod -- if you connect a Creative Nomad to a Windows machine running iTunes, the software won't see it. There is no version of iTunes for Linux machines. But there are ways around that -- just do a Google search for "iPod Linux hacks."

So iTunes (or at least the Mac version) does support other players besides the iPod. But here is gets even trickier: No matter what computer you use, you can't download (or stream) music you bought at the iTunes Music Store to a non-iTunes player. Music you download from the iTunes Store is protected by the Apple DRM (digital rights management) format, which is a proprietary, protected AAC file format that Apple doesn't license to anybody. The only devices that can play those files are ones with the ability to decrypt the Apple DRM, which includes your computer running iTunes, an iPod, an iTunes phone and your speakers connected to AirPort Express. (You can't play them on Roku's SoundBridge, because Apple licensed Roku the iTunes software minus the DRM decryption.)

To play iTunes Music Store files on a portable player besides an iPod, you have to first burn them to a CD as MP3 files. The DRM encoding doesn't make it to the CD. You then rip the now-unprotected files back into your iTunes library and download them to the player.

So now we know which devices will and won't work with the iTunes software. Next, we'll find out what you can do with the software if you've got the right hardware (or the wrong hardware with the right hack).

System Requirements Mac Mac OS X v10.3.9 or later QuickTime 6.5.2 or later 256 MB RAM Broadband Internet (to use Music Store) Windows Windows XP or 2000 500-MHz Pentium class processor or better QuickTime 7.1.3 (included in download) 256 MB RAM Broadband Internet (to use Music Store)