'Differentiation' means making your product stand out, but that doesn't mean it has to be different. As WPP's CEO Martin Sorrell put it: 'Intangible differentiations are becoming more and more important.' In other words, forget the product, just change the way it's advertised. Note that you 'differentiate' your products so that people can 'differentiate' between them. This ambiguity emerged in the mid-19th century, after the word had been borrowed from mathematics, where it means 'the operation of obtaining a differential or differential coefficient'. It always had scientific meanings. In ecology, it's the process by which a species find its own niche in a competitive environment. The first relevant citation seems to be in a 1981 New York Times item about Visa. By the 1990s, it had become a business cliche, but that has not halted its progress. Its latest proponents are teachers, who use it to mean giving harder work to brighter children.