A pirate crew could be made up of many various positions, and it could also have people with different skill levels and reasons for being a crew member. Some of the crew could be hard core pirates from a young age; some could be recently unemployed sailors, and others might be forced into the pirate crew against their will. The size of the crew might vary, based on the ship size, the success of their piracy, and how well they fight.
Captain- The background of many pirates was as a sailor in one of the European navies, and from their service under autocratic commanders, they developed a strong hatred of their incompetent and abusive style.
A pirate captain had to be cut from a different mold, because previous experience had taught most that life at sea was harsh enough without an inexperienced or cruel leader making it worse. He was elected as a sort of president of this shaky democracy, someone already respected for their leadership and navigation skills who would be level-headed and decisive with the pirate crew in the heat of battle.
It was during engagements that this pirate of pirates would be expected to rise above and help bring victory, but in most other occasions on ship, he was more or less another voting member in the pirate crew, delegating most of the everyday tasks to the quartermaster or other junior officer. In these times, he was to be an even-tempered father who maintained the barest level of discipline necessary to hold the family venture together. This father could be voted out and even thrown off if he became passive or wavering, went against the majority vote, became too brutal, or simply no longer performed his duties to the liking of the pirate ship crew.
First Mate- A pirate crew sometimes had this position as the captain's right-hand man and the one who would assume his role if he were killed in battle or could no longer perform his duties. This was often considered the job of a lieutenant in a regular navy, and most pirate crews chose a quartermaster instead of a First Mate.
Quartermaster - Out of their distrust of dictatorial rule, pirates of the Golden Age placed a large portion of the captain's traditional role and power into the hands of an elected quartermaster who became second-in-command and almost a co-captain through his representing the best interests of the crew.
As a foreman, he was in charge of maintaining order, distributing rations and supplies, delegating work, and guarding and dividing plunder. In fighting, the quartermaster decided what ships were worth it and often led any boarding party, ultimately deciding what loot to keep. When discipline or punishment was necessary, only he could give it, but even then it was with the agreement of the captain or the vote of the pirate crew.
In the worst of situations, he was a sheriff enforcing fairness in duels or a judge presiding over jury trials for serious crimes committed among the crew. For all his hard work, the quartermaster received a larger portion of any plunder and would often be asked to command any highly valued ship taken in battle.
Boatswain (bos'n) - This position may be compared to the modern chief petty officer. A ship of any size would require the boatswain to oversee several junior officers who would share his responsibility for the crew's morale and work efficiency as well as the maintenance and repair of the hull, rigging, lines, cables, sails, and anchors.
Gunner - A gunner would be the leader of any separate group manning the artillery. His special skill would be in aiming, but he would oversee the four to six men required to take the gun through the steps of loading, aiming, firing, resetting, and swabbing for the next load. He would also work to ensure the gun crew's safety in avoiding dangerous overheating or excessive recoiling of the weapon. A master gunner would help to coordinate the timing and accuracy of the individual crews, especially when a broadside was ordered.
Powder Monkey - This term was first used in the British Navy for the very young men who made up most gun crews in the 17th century. In contrast to a pirate officer who was elected, these poor souls were forced to perform what was some of the most dangerous work on the ship. They were harshly treated and rarely paid, and if they avoided being mortally wounded in their service, desertion was probably as attractive as having very little hope of being promoted in the pirate crew.
Carpenter - There could probably be no more highly regarded artisan in a pirate crew when your life and livelihood depended on the soundness of the wood around and beneath you. A person in this apprenticed trade would use their skill to not only repair battle damage to masts, yards, hatches, and the hull, but to keep the ship's leaky seams in check with wooden plugs and oakum fibers. He would often have separate quarters combined with a workspace. Each carpenter would usually have an assistant in apprenticeship.
Surgeons, Cooks - Yet another highly valued position, surgeons would often be grabbed from crews of captured ships, although they would not be ordinarily be asked to sign the articles. He would be expected to deal with colds, fevers, or sexual diseases with an assortment of mercurial medicines or other current treatments, and the carnage of battle often required amputations in hopes of saving the wounded.
It seems that the ship was possibly more valued than life or limb when there is no mention of substitute carpenters, but for lack of a surgeon, a carpenter or even a cook would be asked to fill in. A carpenter would be certain to have the similar tools and cutting experience, but a cook as a surgeon would be quite a stretch.
More often than not, a cook would be a disabled pirate who was allowed to stay on ship if he could make food that didn't kill the pirate crew. Perhaps it was felt that if a pirate crew survived his cooking, he could make something to help heal as a stand-in surgeon.
Cooper - If a pirate captain was fortunate enough to have a prosperous career, perhaps he could afford the services of a cooper, a barrel maker. Most everything not in a crate or canvas bag was in a barrel. Using steel hoops and strong wood, the cooper would make containers to keep gunpowder dry, food free of pests, and water and spirits from leaking into the bilge. With a changing environment and the constant shifting of the cargo, the hoops and staves of the barrels required constant upkeep to remain intact and tight.
Musicians - Those who could play drums, bagpipes, trumpets, accordions, fiddles, and other instruments were so well liked that they escaped torture if captured by pirates. With entertainment at a premium on most uneventful days at sea, they would be expected to play a jig to dance to, lead a shanty for work tempo, or provide dinner music. Musicians would usually play prior to and during a battle, blaring out martial tunes, nautical favorites, or simple loud noise to inspire the crew. Bartholomew Roberts wrote a provision in his articles stating that regular Sabbath rest should be provided for his musicians. Roberts was known for his good treatment of his pirate crew.