Even at its most basic, game music has always had a quirky appeal. Perhaps it's a stretch to even call it music, but the rhythmic bleep-BLOOP of Pong, one of the earliest video games, is both ever-changing and meditative. But if you haven't kept up with game music, you might wonder how it evolved from that to Tin's "Baba Yetu," a rousing choral work written as a Swahili version of the Lord's Prayer.

The history of game music is in part the story of how knotty, musical concepts that were once the domain of avant-gardists became the everyday soundscape of teenagers. Composers Karlheinz Stockhausen and Witold Lutoslawski experimented in the mid-20th century with nonlinear compositions, writing music to be played in random sequences and eliminating the notion of beginning, middle, and end. It didn't really catch on. But it's an idea that has found its place in game music, which is nonlinear by necessity. Players' choices require branching narratives, and the music has to adapt to changes in action and emotion.

"You're never 100 percent sure what will be happening on screen at any time," says Danny Baranowsky, who scored the music for the recent hit Super Meat Boy. "It's important to score so that every second of the track could potentially fit the action on the screen."

Mozart developed a musical dice game called Musikalisches Würfelspiel in which chance determined how a minuet was performed. Such games were popular in their day, but the fad died and interactive music suffered a centuries-long lull. Then came Koji Kondo, Nintendo's main in-house composer in the 1980s. His score for Legend of Zelda: Ocarina of Time is a highlight of early game music interactivity. In what's probably the best use of an ocarina since the Troggs, players get ahead by performing songs on the controller, shaped like the ancient instrument. It paved the way for the slew of Rock Band, Guitar Hero, and DJ Hero games.

Kondo is best known for Super Mario Bros., arguably the most iconic music in game history. A quarter-century after it's release, it's a rare soul under 45 who doesn't recognize the bouncy, preternaturally catchy melody. Kondo's scores are all the more impressive because he wrote them in the 8-bit era of games. Music has long been defined in part by the limits of technology, and 8-bit music is all limitations—hence the beeping, sing-song tone.

Technology marched on; 8-bit gave way to 16-bit, to 32-bit, and so on. If 1980s game music was about limitations, Nobuo Uematsu, the main composer of the Final Fantasy series, showed what could be done once some were lifted. Since 1989, he's been the superstar of game music and probably the first game composer subject to a tribute album.

As musical capabilities increased, big names signed on. Trent Reznor's Quake and Hans Zimmer's Call of Duty: Modern Warfare 2 are some of the results. Conversely, game composers crossed over. Michael Giacchino made his name with the Medal of Honor series, and went on to do the music for TV's Alias and Lost and the last Star Trek movie.