THE CLASSIC VIDAL SASSOON

THE original, short geometric bob, synonymous with Sassoon and Mary Quant, above, is short in the back and longer in the front.

You need a highly skilled stylist for this unforgiving cut — too high at the back and you’ll look like someone hit you from behind with a shovel; too low and it will make your head look overly round.

Similarly, taken too high at the front it will destroy your facial proportions. And, of course, there is no room for mistakes in the sharp line, which must be perfectly straight.