A three-track EP released in September 1979, simply titled 3, set the stage for everything that would follow for U2. Bono's lyrics were by turns introspective and anthemic, while the Edge's two-note chord-driven harmonics were already in place.

There was room to grow. Bono was still performing with an of-the-moment post-punk attitude. And their fidgety rhythm section, then more directly influenced by Echo and the Bunnymen, would continue to evolve from this nascent sound, as well.

But that was entirely understandable. After all, they'd only actually been called U2 for a short time at this point, having shifted from a six- and five-man lineup that was first known as Feedback and then the Hype. The trimmed-down quartet, rounded out by bassist Adam Clayton and drummer Larry Mullen Jr., won a talent competition sponsored by Guinness in 1978, then aced an audition with CBS Ireland and, later, earned an opening spot on several tours.

The EP was a culmination of that quick rise to regional notice, after paying their dues in teen bands dating back to 1976. And, in at least one instance, it has continued to play a role in their career, even as U2 became an international sensation.

Still, things started awfully small. 3 was produced as an Ireland-only release with an initial pressing of just 1,000 copies, then reissued six times as their fame grew. The track listing was actually determined by a listener poll on a local radio show, which found callers most interested in "Out of Control" as the lead-off song.

Bono, however, was already wrestling with much bigger issues. He wrote "Out of Control" during a period when he was still wrestling with his mother's death a few years earlier. "I said, 'Well here we are,'" Bono remembered in a talk with Musician. "I'm 18, and the two most important things in my life -- being born and dying -- are completely out of my hands. What's the point? At that point in my life, I had a lot of anger and discontent when I couldn't find answers. It was violent, but mentally violent."

The lead track, along with "Stories for Boys" from the 3 EP, were eventually rerecorded for U2's first full-length album, 1980's Boy. (The same child, now a Dublin-based photographer himself, appeared on the cover of both records) "Out of Control" would later find a home on 2003's U2 Go Home: Live From Slane Castle, Ireland concert release, as well.

The Edge acquits himself particularly well on the song's spacious, yet menacing solo -- and, even today, he sees it as a career fulcrum. "‘Out of Control’ was really the point where the songwriting started to become more exciting," he said in U2 by U2. "It was still effectively the same process, but there was just more form to it."

Watch U2 Perform 'Stories for Boys' in 1980

3 was rounded out by "Boy-Girl," a live version of which was later used on the flip side of U2's "I Will Follow" single in 1980. Initially, all three songs were a part of their concert performances, continuing as a group through the Boy tour's conclusion in 1981, when they had been clustered together to end the main set.

"Boy-Girl" would be played fewer than a handful of times thereafter, while "Stories for Boys" was memorably referenced in a line from their 2004 single "Vertigo" -- leading Bono to occasionally insert a snippet of the older song during the concert dates that followed. But the last regular appearance for "Stories" had been on the October tour in 1982. The same couldn't be said for "Out of Control," which rotated with "Gloria" as the opener during the War tour and remained a stalwart presence into the current decade -- including an appearance during a 2011 set at Glastonbury.

Meanwhile, 3 has become a cherished rarity over the years, having been first released on CD in 2008 as the bonus disc with the Boy reissue. Over the years, the original vinyl record has sold for hundreds of dollars.

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