It's 4/5. '45. Little slabs of sunlight cut on seven inches of wax. From rock 'n roll to roots reggae and post punk to soul, it was the great equalizer: the domain where the upstart musician could go toe to to with the stars. Of course some of the biggest names were masters of the form - look no further than The Beatles' and The Stones' killer run of singles through the sixties for just one example - tucking away stellar tracks on the flip that wouldn't show up anywhere else for years, but figures like The International Submarine Band and The Del-Vetts would come out of nowhere with records like Sum Up Broke and Last Time Around and drop heat of their own. Although it would increasingly lean on the LP format in years to come, rock 'n roll was born on the 7" single.
If there was one genre that dominated the form, then surely it must have been reggae. From the Wailing Souls' Without You to Augustus Pablo's East Of The River Nile and Zap Pow's River Stone, there was a practically endless stream of brilliant 7" singles flowing from Jamaica for decades on end.
The other obvious contender is the soul/funk continuum, boasting James Brown's run of People Records (not to mention his own records!) and Sly Stone's genre-defining rubbing shoulders with The Beginning Of The End's Funky Nassau and Dark Skin Woman by Sir Mack Rice. This isn't even taking into account the winding catalogs of Stax, Motown and Philadelphia International.
Post punk had it's own horde of stone tablets like the five-pronged attack of electronic records coming from the likes of The Human League, Throbbing Gristle, Thomas Leer, The Normal and Cabaret Voltaire. The flipside was twisted records like The Pop Group's She Is Beyond Good And Evil, PIL's Public Image and the Minutemen's Paranoid Time (indeed, this the era that you'd get loads of 7" records that were essentially micro-LPs, records like Minor Threat and the Meat Puppets' In A Car).
In the nineties you had things like Beck's Deadweight come out on 7" (and why couldn't White Gold have been the b-side to The Dandy Warhols' Get Off like it was on the CD?). There were loads of records that would have lent themselves to the format, even if they never did surface. Records like Roller Rinks & Chicks by Freddy Fresh, Scott Weiland's Jimmy Was A Stimulator, The Orb's 7" Edit of Toxygene... practically any of the dusted records of the era would have lent themselves to the form.
In the digital era, a lot of exclusively 7" music finally found its way onto other formats, via expanded reissues or compilations like the Nuggets box sets. Labels like Strut and Soul Jazz chronicled entire genres/scenes around the 7" single, breathing new life into the form. And there's still nothing quite like a good b-sides collection...