By Chris Heard BBC News Online entertainment staff

The Sugarhill Gang's first record has had an enduring impact

The success of Rapper's Delight came after the scene had grown on the streets of New York for several years. But it was not universally liked by fans or critics.

Purists dismissed the group as manufactured and said they did not represent the scene's true artistry - but most now agree it was hugely important.

Rapper's Delight was technically the second rap record, lagging a few weeks behind The Fatback Band's King Tim III (Personality Jock).

The Sugarhill Gang on Top of the Pops

Built on a sample of Chic's disco hit Good Times, it featured the vocals of trio Wonder Mike, Big Bank Hank and Master Gee.

Sugarhill label owner Sylvia Robinson discovered Big Bank Hank rapping behind the counter of a New Jersey pizza restaurant and asked him and his colleagues to audition in her car outside.

HIP-HOP'S EARLY PIONEERS Jamaican DJ Kool Herc is credited with starting hip-hop turntable culture, built on breakbeats and the volume of the sound system Fellow DJ Grandmaster Flash used technology to advance DJ culture, inventing the cross-fader and creating his own mixing desk Afrika Bambaataa broadened the scope with electronic and rock influences Timeline: 25 years of rap

But any suggestion the record was a novelty were to be proved spectacularly wrong.

It went multi-platinum, eventually selling more than eight million copies worldwide, and set the pace for the rap recording industry.

According to a forthcoming book, Chic were "absolutely amazed" when they first heard Rapper's Delight played in a New York club within a few weeks of Good Times being a huge worldwide hit.

Former Chic guitarist Nile Rodgers told author Daryl Easlea he believed the new version of their tune would be "only something that was distributed among DJs and not for sale".

"He was quickly on the phone to [Sugarhill owners] the Robinsons at the time saying, 'what on earth is this'?" according to Mr Easlea, author of Everybody Dance - Chic and the Politics of Disco.

Run-DMC were among hip-hop's other early pioneers

By the time it made the US charts, hip-hop had been flourishing in New York as an underground culture for about five years.

Young music fans in the south Bronx discovered the emerging scene at "block" parties where legendary DJs such as Kool Herc, Afrika Bambaataa and Grandmaster Flash played a mixture of soul, funk, disco and rock records that inspired the movement.

Jamaican Herc is credited by many hip-hop historians as being the scene's most important founding figure.

He focussed on the instrumental and percussive "breakdowns" that were part of the make-up of a song. These elements came to be known as "breakbeats" or "breaks".

Herc recognised that dancers responded well to the breaks, and sought to extend them by repeating the break on a second turntable as the first one finished.

As the second break ended, he would then return to the first, creating a seamless - and potentially infinite - rhythmic pattern.

THE HIP-HOP YEARS 1974-1984: The "old school" years - from the birth of hip-hop at South Bronx parties to the arrival of Run-DMC 1984-1986: A two-year experimental period spearheaded by Run DMC's groundbreaking Raising Hell album 1986-92: Rap's "golden age", noted for the technical, stylistic and lyrical innovations of Public Enemy, KRS-One and De La Soul

The scene attracted an inventive, athletic style of dancing - known as break dancing - performed by break-boys or B-boys. Graffiti art, a form that had emerged in New York in the early 1970s, also became integral to the movement.

BBC Radio 1Xtra black music expert Jacqueline Springer said Rapper's Delight was important because it was the first commercially successful rap record.

"It alerted the mainstream and broader white society that the genre was in existence," she says.

"It was a good record. People forget with the radio edit, but it was about 16 minutes long. When it first came out, it was played in its entirety.

'Entertaining'

"It samples a disco break and it adheres to the DNA of early rap. Now we want our rap to be a lot more frenetic, but this entertained the crowd and buoyed them along, and that stands as its testament."

Hip-hop expert and journalist Angus Batey said Rapper's Delight was not seen as representative of the newly-emerging live scene by die hard fans.

But its success, selling out quickly across New York and further afield, showed there was a big appetite for the recorded art form.

"In the long run, it's been seen as a classic," says Mr Batey.