The smaller pinnace is a light boat, propelled by sails or oars, formerly used as a "tender" for guiding merchant and war vessels. In modern parlance, pinnace has come to mean a boat associated with some kind of larger vessel, that doesn't fit under the launch or lifeboat definitions. In general, the pinnace had sails, and would be used to ferry messages between ships of the line, visit harbors ahead of the fleet with messages of state, pick up mail, etc. The pinnace was also widely used during the pirate infested 1600s, mostly in the Caribbean area. The Spanish favored them as lightweight smuggling vessels while the Dutch used them as raiders. Pirates frequently used them as scouts and for night attacks since they were small, reliable, and extremely quick, even against the wind.
The second, larger type was developed by the Dutch during the early 17th century. She had a hull form resembling a small "race built" galleon, and was usually rigged as a ship (square rigged on three masts), or carried a similar rig on two masts (in a fashion akin to the later "Brig"). Pinnaces saw use as merchant vessels, pirate vessels and small warships. Not all were small vessels, some being nearer to larger ships in tonnage. This type saw widespread use in northern waters, mainly by the Dutch, as they had a shallow draught.