can't agree with the comments about piracy.
prize-taking was widely practiced and well understood by all concerned. The 'Jack Aubrey' novels of Patrick O'Brien have a constant backdrop of the various pitfalls and restrictions a captain risked; prizes would be bought by an Admiralty commission and put back into service, or sold at auction, and the cargoes and fitments valued and disposed of similarly.
however, the owners of a neutral ship, or one protected by an agreement or consent of a neutral government, or in a protected trade, could - and frequently did - sue captains for damages, and the Admiralty would not intervene.
a captain was also expected to provide considerable hospitality for his officers and visiting captains, and ( if he saw fit ) to provide additional powder, shot and other munitions over and above the ships' complement. This was all funded from prize money.
the next step down, so to speak, was a vessel rated as 'His Majesty's Hired Ship'; effectively a chartered private vessel with certain contracted rights as to Admiralty resupply, and most - though not all - the duties and rights of a warship.
the next category, a 'privateer', or 'letter of marque' vessel, was a licensed ship authorised by a belligerent government to operate against the shipping of enemy nations. The only income would be the value of prizes, which might be bought by the Admiralty prize commission, or dealt with as the captain or owner saw fit. Crews and passengers of prize vessels could expect to be ransomed or otherwise dealt with as prisoners of war. However the captain and crew of a privateer risked being hanged as pirates in the event of attacking a third party and coming off worst, and they were generally regarded as little better than pirates, but were at least regarded as legal in their home countries and allied territories.
a pirate would be an unregistered vessel recognised by no national navy, drawing no resupply from any legal source and attacking any targets it saw fit, frequently killing the passengers or crew for lack of any other real alternative.
these distinctions were well understood by all concerned, in an age when it was regarded as quite normal and proper that 'patriotism should have its reward' and had been in existence since at least the latter part of the 17th century, if not before. Sir Francis Drake was a privateer, and far from being a general brigand could, under certain circumstances, be regarded as the representative of the Crown.
''the stopes soared beyond the range of our caplamps' - David Bick...... How times change .... oh, I don't know, I've still got a lamp like that.