Porter is a dark style of beer originating in London in the 18th century, descended from brown beer, a well hopped beer made from brown malt. The name came about as a result of its popularity with street and river porters.
The history and development of stout and porter are intertwined. The name “stout” for a dark beer is believed to have come about because a strong porter may be called “Extra Porter” or “Double Porter” or “Stout Porter”. The term “Stout Porter” would later be shortened to just “Stout”. For example, Guinness Extra Stout was originally called “Extra Superior Porter” and was only given the name Extra Stout in 1840.