Special Bitter or Best Bitter

Ale is a type of beer, brewed using a warm fermentation method. In medieval England, the term referred to a drink brewed without hops. As with most beers, ale typically has a bittering agent to balance the malt and act as a preservative. Ale was originally bittered with gruit, a mixture of herbs or spices boiled in the wort before fermentation, before hops replaced gruit as the bittering agent.

Source: Wikipedia