Boy contains songs from the band's 40-song repertoire at the time, including two tracks that were re-recorded from their original versions on the group's debut release, the EP Three.

Thematically, the album's lyrics reflect on adolescence, innocence, and the passage into adulthood,[2] themes represented on its cover artwork through the photo of a young boy's face.

[1] Lillywhite employed a creative, experimental approach as the producer, recording smashed bottles and silverware skimmed against a spinning bicycle wheel for sound effects.

[2] With the band members still inexperienced at that point and manager Paul McGuinness giving them autonomy in their music-making process, Lillywhite speculated that he had more influence over the sound of Boy than any other producer of any other U2 album.

[1] Bono was displeased with the vocal performances that he gave in the studio when wearing headphones, and as a result, he changed his approach to sing into a handheld microphone in the control room while listening to playback of the music at high volume.

[2] The Edge recorded all the songs using his Gibson Explorer guitar,[12] and he drew inspiration from music he was listening to at the time, including Television and early Siouxsie and the Banshees.

For example, "Shadows and Tall Trees" takes its name from a chapter title in the dystopian William Golding novel Lord of the Flies, and "The Ocean" mentions Oscar Wilde's novel The Picture of Dorian Gray.

[citation needed] Music author and ambient historian Mark Prendergast writes that Boy has "an aquatic quality, contrasting anthemic rock songs with brooding instrumental passages of spray, fine drizzle and lapping waves".

[15] He further highlighted Lillywhite's addition of musique concrète sounds, namely milk bottles and scraped bicycle spokes, to "I Will Follow", and commented that the Edge's "unconventional approach" to his Gibson Explorer throughout the record "was to eschew blues influences for echoed chords and sustained harmonics.

The result of these processes gave Porter the "raw material" to continue, though some areas of the images did not distort well and were subsequently marked up with a black pen.

"I Will Follow" peaked at number 20 on the Billboard Top Tracks rock chart in the US,[25] becoming a hit on college radio and establishing a buzz surrounding the group's debut.

Paul Morley of NME called it "honest, direct and distinctive", adding that he found it "touching, precocious, full of archaic and modernist conviction".

[36] Betty Page of Sounds said that they "achieved a rare mixture of innocence and aggression", and described the album as "an overall feeling of loving care and energy intertwined with simplistic and direct hooks and chords".

[34] Lyndyn Barber from Melody Maker hailed it as a "rich" record, writing that "Boy is more than just a collection of good tracks assembled in an arbitrary order", and that it had "youthful innocence and confusion".

[37] Robin Denselow of The Guardian wrote that it was a "strong debut album", praising Lillywhite for helping U2 improve since a live show that the reviewer attended.

Walston of the Albuquerque Journal said that U2 "knows how to nurse a listener along, toying with tempo and chord structures just enough to sound original but not overly avant garde".

[40] Terry Atkinson of the Los Angeles Times called Boy a "subtly ravishing first album, by turns pretty, propulsive, playful and irresistably catchy", while further describing it as "supple and melodic, but tough and vital as well".

He praised Lillywhite's production for creating an "eerie ambience" and said of the band, "U2 have the musical chops, a compelling vocalist... and most importantly 4-minute pop songs that sound at once concise and infectious".

Anderson thought certain songs were too long or too short, but believed U2 distinguished themselves from their peers with their spirit and humanity, making "a most refreshing splash in the New Wave".

[43] Dave Marsh of Rolling Stone said the record's music was "unpretentious and riveting" and called U2 "easily the best Irish rock band since Van Morrison's original Them troupe".

[31] More critical was Robert Christgau, who dismissed the album in his "Consumer Guide" column for The Village Voice: "Their youth, their serious air, and their guitar sound are setting a small world on fire, and I fear the worst.

[46] On an otherwise successful American leg of the tour, Bono's briefcase containing in-progress lyrics and musical ideas (which were intended for the group's second album, October) was lost backstage during a March 1981 performance at a nightclub in Portland, Oregon.

[61] In 2020, Rolling Stone included Boy in their "80 Greatest albums of 1980" list, praising the band for creating "an incredible collection of songs steeped in lost innocence and apprehensions about entering the adult world.

[50] Reviewing the 2008 reissue, Q appraised Boy as a remarkably ambitious debut, noting a distinct "adolescent energy" and "gauche charm" to the album,[56] while Mojo said it retained its "palpable ardency" years after its release.

Writing for Entertainment Weekly, Bill Wyman found it "heady" but "erratic",[53] while Chicago Tribune critic Greg Kot described the album as "callow post-punk that owes a lot to Joy Division and early Public Image Ltd."[52] According to Ann Powers in the Spin Alternative Record Guide (1995), the album "established what might be called [U2's] revelationary reputation, hints at the impulse toward faith (after all, its hit was 'I Will Follow'), but mostly communicates confusion of the adolescent variety.

"[58] Uncut critic David Quantick was more negative in his reappraisal, recalling his enjoyment of the album in 1980 as a "rockier" contemporary of Joy Division and Echo & the Bunnymen, in spite of Bono's "preening" vocal performance, but upon listening to the reissue, felt "shock at how bad it is".

[64] All tracks are written by U2Early vinyl and some cassette copies have an unlisted and untitled 30-second instrumental sample at the end of the album (following "Shadows and Tall Trees") of "Saturday Night", a song that would later become "Fire" on the 1981 record October.