Surprisingly, considering the long history of the fermentation of fruit to make wine, cider, perry, and pyment, the use of fruit as a beer ingredient was relatively rare until recently. The only traditional beer style made with fruit is the Fruit Lambic, traditionally mixed only with sour Belgian cherries to make a Kriek. Berliner Weisse was traditionally blended with a fruit or herb syrup before drinking, but fruit was not used in the brewing process itself.
Modern home brewers, of course, will throw just about anything into their fermenters to see what comes out, and with the growth of the American home and craft brewing movement a number of fruit beers have emerged on the scene, usually based on existing beer styles with an addition of a single distinctive fruit. At least one distinctive new style has emerged using fruit; the Pumpkin Beer or Pumpkin Ale brewed by many small American breweries each fall, which sometimes is brewed with pumpkin and sometimes just with the spices associated with pumpkin pie.
Until more distinctive categories emerge, most other fruit beers are considered specialty beers.