The brig was probably the most common rig for smaller vessels of under 200 tons during the 18th century. The brig had two masts. The fore mast was completely square-rigged like its equivalent on a ship or barque. The main mast was rigged with a large fore-and-aft sail (the spanker or driver) with square sails above this. The main mast was rigged similarly to the mizzen of a ship, but was taller. Brigs were usually used in coastal and short sea trades. The collier brigs became closely associated with the London coal trade, bringing fuel from the Tyne and Wear to the Thames for domestic and industrial use.

The brig had the disadvantages of all square-rigged ships. A relatively large crew was needed, as setting or furling the sails required the sailors to go aloft. This made it more suitable to long ocean voyages, where the winds were constant, than coastal work where there were more frequent changes of direction requiring work on the sails. Another disadvantage in the coastal trade was that a square sail vessel could not sail in a direction as close to the wind as a fore-and-aft rigged one.

The brigantine had a mixture of square and fore-and-aft sails. Its fore mast was rigged like that of a brig, with square sails. But the larger main mast had just one big fore-and-aft sail, the driver.