Unique Selling Proposition

The Unique Selling Proposition (also Unique Selling Point) is the marketing concept that was first proposed as a theory to explain a pattern among successful advertising campaigns of the early 1940s. It states that such campaigns made unique propositions to the customer and that this convinced them to switch brand.
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the particular quality, feature or benefit of a product which a competitor's product, although similar, cannot or does not offer; commonly referred to as the USP.

a marketing claim based upon a distinctive product feature or unique element in the marketing - mix (see gaining competitive advantage) (see unique emotional proposition).