When used referring to beer, ESB stands for Extra Special Bitter. This is a style of ale, also sometimes called a Strong Bitter. This style of ale originated in England. An ESB is a rich, full bodied "bitter" ale, copper to golden in colour. The hops should be medium to strong, complimented by a sweet flavour of residual malt. This is a middle-of-the-road style, heavier and more flavourful than a regular bitter or a pale ale but still light and crisp in comparison to a porter.

ESB was originally brewed in The Griffin Brewery, an historic location where beer of one form or another has been brewed since 1654. Fuller's has been the operator since 1845 and makes an ESB which is considered the original.