How Spotify Works

Spotify isn't a new technology. It's actually been around since 2008, when a company named Spotify AB launched the Spotify service in Sweden. Since then, the company has been negotiating licensing issues and slowly rolling out to other countries, including Finland, the United Kingdom, France, the Netherlands, Spain and, as of July 2011, the United States.

Given the country's technological history, it's no surprise that Spotify emerged from Sweden. The Swedes have one of the fastest broadband Internet systems in the world, as well as some liberal attitudes toward copyright laws.

It's partly those reasons that the Pirate Bay, a Web site that provides file-sharing links (many of which lead to stolen copyrighted material), started in Sweden. It isn't that Swedes are predisposed toward thievery; it's that their super-fast Internet and tech-savvy lifestyles have created an expectation for instant access to any material they desire.

Pirate Bay helped to foster that mentality, but Spotify hopes to legalize it. Spotify actually borrows many of Pirate Bay's technologies to share music. Only with Spotify, the record companies (many of them, anyway) have given Spotify their blessing to share music, so long as they receive revenue. And Spotify, of course, garners much of its income from the advertisements it streams during commercial breaks (more on this later).

Spotify is a hard sell in some areas, such as America, where music labels are reluctant to let online entities share their catalogs. After lengthy negotiations, however, all four major labels (EMI Group, Universal Music Group, Sony Music Entertainment and Warner Music Group) signed on to let Spotify share music with its users.

As Spotify continues to spread a legitimate alternative to illegal-file sharing, the company might just become the next big thing in the digital music revolution. It offers people instant access to specific songs, from just-released electronic trance tracks to 1920s jazz, and much, much more. It does so without placing huge demands on users' pocketbooks and without the weight of conscience for those who had resorted to illegal music pirating.

Just how the company pulls off this feat is another story altogether. On the next page, you'll see exactly how Spotify works -- and how the company wants to make you forget about CDs, tapes and other digital music services, forever.

If you've ever used iTunes, Spotify will immediately give you a feeling of déjà vu. Its layout and interface is similar to that of iTunes, letting you browse music by artist, album, song name, genre, record label or playlist. You can also locate artists and songs through keyword searches.

What's more, Spotify also finds music on your local hard drive. So when you execute a search for Johnny Cash, you'll see the copy of the song "Folsom Prison Blues" stored on your computer, in addition to any other different versions of the song that might exist in Spotify's library. Spotify can import your existing digital music collection into its catalog. That includes all of your MP3, MP4, M4A, M4R and most iTunes files, with the exception of protected M4P files. And if the tracks are protected, Spotify will try to find the same song in its online library so you don't have to go without it.

Once you find the music you want, you simply click play and then Spotify instantly streams the music directly to your speakers for free. Unlike some music sites that randomly select music similar to an artist or song you select, Spotify allows you to pick and play individual tracks, which you can add to personalized playlists.

Free accounts have significant limitations. New accounts can listen to ad-laced content for up to 20 hours per month. After a six-month trial, you can only stream 10 hours of music per month and play the same track up to five times, all on your local computer only. Music playback is occasionally interrupted by audio advertisements that last about 30 seconds (and if you attempt to turn down the volume on these blaring ads, the ad merely pauses until you increase the volume again).

To nuke the advertisements and hear an unlimited amount of music, you can ante up $5 monthly for an Unlimited account. For $10 per month, however, you'll score a Premium account that lets you play music on a mobile device (including iPhone, iPod Touch, Android, Symbian, Windows Mobile and Palm), and download and store tracks to your computer or device so you can access them offline when you have a spotty or nonexistent Internet connection.

Spotify emphasizes music sharing, letting you tell your friends that you're listening to the new Emancipator album through either Facebook or Twitter with just a click. In fact, Spotify's recent partnership with Facebook underscores how much the company wants its users to share music with all of their friends (using its services, of course) to keep the music (and commercial breaks) playing non-stop.

As of this writing, Spotify requires you to use your Facebook login information to create a new account. Then, by default, Spotify will share your playlists with your Facebook friends. You can toggle off this feature if you don't like it, but it's yet another clue as to how Spotify hopes to use Facebook to stay front and center in the digital music scene.

By now, you can see that Spotify is a unique blend of local music playing software, random Internet radio and customizable, on-demand song jukebox. But making all of these capabilities work together flawlessly took some serious planning and technological expertise. Keep reading to find out exactly how Spotify keeps the songs spinning and the party pumping without any interruptions.

Most Internet music players work in a similar fashion: You pick a musician or song and then the site begins streaming the song's data to your computer. From both a technological and end-user perspective, this feat has some drawbacks.

With a less-than-speedy Internet connection, the high amount of data involved in streaming audio playback results in pauses, skips and, sometimes, complete stops. This exasperation alone will drive you, screaming and in tears, back to your CD collection.

Spotify uses some nifty tricks to avoid playback errors. Instead of constantly bogging down its own company computers and Internet bandwidth to send songs to millions of end users, it relies heavily on a peer-to-peer (P2P) network to stream audio, which works in the same decentralized manner of infamous torrent sites such as the Pirate Bay and Kazaa.

When you select a song, Spotify's computers immediately begin sending the data to your computer. Simultaneously, it looks for other Spotify users who have the tune on their computers. When it finds the track, it commands the Spotify software to send bits of the song to your computer, all of which takes a load off of Spotify's central servers and Internet connection. Spotify doesn't publicize how much data it acquires from individual users to help feed the P2P network, but in most cases, it's unlikely you'll notice any lag in your Internet speeds as a result.

Spotify uses another trick to keep playback speedy. It caches (or stores) the songs you listen to most right on your hard drive, which means your computer plays the song instead of Spotify. You can adjust the size of the cache, but by default, it's set to a hefty 10GB, enough room for hundreds of tracks. That's in addition to the specific songs you download with a Premium account, by the way.

What's more, Spotify is smart. The site knows that most of its users listen to albums from beginning to end, so if you start playing the first song of DJ Shadow's latest album, Spotify beings preloading subsequent tracks, too, so that you never experience playback delays.

All songs streamed from Spotify sources are in the Vorbis format. Like MP3s, this format is compressed to make for smaller, more easily transferred files. Most songs stream at about 160kbps (kilobits per second), although many songs available to Premium users stream at a higher-quality 320kbps.

Geek-speak aside, Spotify obviously offers a lot of different ways to play a huge variety of music. But is this really a panacea for all things in the digital music revolution? Keep reading to discover how Spotify stacks up to other services -- and how in some cases, it might not measure up to the competition.

Spotify's biggest strength is simple: It lets you play just about any song instantly without having to purchase or download it from a legal (or not-so-legal) source. But there are some drawbacks, too.

Licensing conflicts continue to hamper the experience for some users. Although Spotify likes to brag about its huge library, your impression of the catalog's completeness will depend entirely on your music tastes. For example, as of this writing, you won't find artists like Pink Floyd, AC/DC, Led Zeppelin, Metallica or the Beatles in the catalog (in general, the Spotify library is a very fluid thing, with songs' availability dependent on the whims of artists and record companies). If you have offbeat or even slightly eclectic music preferences, you might find that to Spotify, your favorite musicians simply don't exist.

Plus, many bands allow playback of only parts of their discography, so you may find a few songs by North Mississippi Allstars, but you'll be out of luck on many of their tunes. And if you're not already familiar with their back catalog, you might miss out on their best music.

Sometimes, an album will be missing only one or two songs, which are shaded in the song list. Try to play those tunes, and you'll see a message that says, "The artist/label has chosen to make this track unavailable. If you have the file on your computer you can import it." Instances like this could make it difficult to create complete, comprehensive playlists in Spotify.

If you upgrade to the paid services, you'll be paying every month regardless of whether you use the service or not. At $120 per year for the Premium service, that's roughly 10 to 12 albums you could buy from a vendor and actually own, instead of pushing money into Spotify's service, from which you basically rent your music (unless you decide to buy tracks from the company).

And if you like the feeling of supporting your favorite bands financially, it's worth noting that artists receive a higher cut of dough if you simply buy their album instead of paying Spotify to stream it to you. In one oft-cited example, Lady Gaga pocketed only $167 for roughly 1 million plays of her hit song "Poker Face" on Spotify [source: Guardian].

On the other hand, Spotify is renowned for helping people find alternate or cover versions of their favorite songs. Type in "Folsom Prison Blues," and you'll see live versions and covers by other well-known (and not-so-well-known) musicians. In fact, one of the company's big strengths is that its reach helps lesser-known artists expose the broader world to their brand of music.

Unlike Pandora, Spotify lets you skip an unlimited number of songs, so you can always bypass the stuff that doesn't appeal to you without any hesitation. However, Spotify doesn't automatically build playlists based on your preferences, although you can connect your Spotify account to Last.fm. Spotify uses this integration to learn which songs you like best.

Spotify is jammed with other features that we haven't covered yet. On the next page, we'll give you some tips on how to access the best of this service to keep the beat thumping and your toes tapping.

Spotify has so many features (and so many songs) that it's easy to get lost amid this mountain of digital music. But there are a few tips that will help you listen with less frustration.

Spotify's search engine sometimes requires a bit of extra work on your part. The search feature isn't as flexible and forgiving as, say, Google, so if you misspell part of a song or band name, you may not see any results. Even an extra space between letters can totally throw off the system, so double-check your verbiage if your results list is empty.

On the other hand, type in a popular band or song, and you may be overwhelmed by the number of entries you see. Click the top menu bar to sort by song, album, artist, song length or popularity, and then press the PGUP or PGDN keys to move quickly through results (this is much faster than scrolling).

There are other pertinent keyboard shortcuts, too. Press the spacebar to pause or start playback. Press CTRL and the up or down arrows to control volume.

Note that Spotify's huge library often pulls up multiple versions of the same song, but it hides them. Look just to the right of the song title and you may see a small arrow. Click that arrow to reveal the other versions.

Spotify is so popular that it has spawned a plethora of related sites and apps. For starters, because Spotify's "Artist Radio" (which is a bit like Pandora) is only rolling out to Spotify users incrementally, you can get a preference-based experience by opening Spotify and visiting a third-party (not sponsored by Spotify) application. Examples include Echofiapp.com, Spotibot.com and Spotiseek, all of which play artists similar to your favorites.

Another site, Spotimy.com, offers a way to discover critically-acclaimed music. Just as with popular Metacritic.com, Spotimy scans aggregated reviews all over the Web and highlights artists with high scores. You can then select and play those albums instantly.

Like all other music services, Spotify has both strengths and weaknesses, and depending on your tastes in music (and technology), it may (or may not) offer everything you need. The best way to find out is to dive in and test drive Spotify's massive music collection.