Pop music and Dance music, as we know them, emerged in the period following WW1 and The Great American Plague - 1919.

They originated from the early Jazz of New Orleans and evolved into "Syncopated Music".

For the first 20 years, the BANDS held sway. Pop and Dance had ARRIVED.

Broadly speaking, Pop (a term that did not actually emerge until the '50s) was defined as music made mainly for listening to - but you could also dance to it. While Dance was music made for dancing to - but you could also listen to it.

The essential difference was - and continued to be - whether or not it had vocals.

Pop and Dance ruled, side-by-side, for 70 years. In 1990, Pop finally DIED, killed by the greedy record companies that fed off it. Dance moved in to fill the void with "Trance" music - but after another decade, it too fizzled out.

During those eighty years, little changed - f'rinstance: "There is a fascination about well played modern dance music. The melody is there - and an unfailing rhythm. But around them is woven a texture of quaint effects, so numerous and unexpected as to give one great respect for the clever people who think them all out."

A fine description of Trance music - except it actually comes from a record cover which, on its reverse, has instructions for the care of your WIND-UP GRAMOPHONE!

So did NOTHING change during the Twentieth Century? Well, one important thing did - technology.

Shellac gave way to vinyl - mono gave way to stereo - and analogue gave way to digital.

But the most important development came in 1927 - the invention of ELECTRONIC recording.

Before then, bands and orchestras had been forced to gather around a giant horn - not dissimilar to the one singers had to BELLOW through at live gigs.

And the resulting records sounded like they had been strained through a wet sock.

But now, vocalists could nuzzle up to a moving-coil mic and purr lovingly into it - and be heard all around the hall.

SOUND QUALITY had arrived - and for the first time, the recording industry came to be taken seriously.

Before '27, gramophone records were a tinny-sounding gimmick - a novelty. But now, they became the medium through which Art Deco music could be enjoyed by millions.

And it was a Golden Era for Pop and Dance. The frenetic Charleston was giving way to the more accessible Fox-Trot. Dance halls were springing up everywhere. Most people met their future Life-Partners there.

But over the passing of time, this EXCITING music has largely been fo