Why were Kraftwerk such a colossal success?

Everything about Kraftwerk was odd. They had no front man, they seemed to play no instruments and their strange, electronic music owed nothing to blues, soul or any of the other forms of music that underpinned 20th-century pop. Instead, a Kraftwerk gig consisted of four rather gauche-looking fellows from Düsseldorf standing in a row, each poking at a synthesiser, as a strange, apparently unconnected series of images appeared on screens behind them. A Kraftwerk album could be just as confounding. The cover of the 1977 album Trans Europe Express featured a portrait of the band. In suits and ties, they looked more like the partners at an accountancy firm than an electronica band.

Odd they may have been, but Kraftwerk were revelatory for being the first group in history to make purely electronic music and their sound — a torrent of synth sounds, drum machines and electronically mangled voices — was so different as to sound almost alien.