Nami, also known as "Cat Burglar" Nami, is a fictional character in the One Piece franchise created by Eiichiro Oda. She is based on Ann and Silk, two characters from Oda's previous manga Romance Dawn. She is introduced as a thief and pickpocket who possesses cartographical, meteorological, and navigational skills. At first, she is a subordinate of the fishman Arlong, until she is eventually freed of this service and permanently joins Monkey D. Luffy.

In the series, Nami is the Straw Hat Pirates' navigator, who dreams of drawing a map of the entire world. Despite her initial distrust of pirates, Nami eventually changes her mind after being around Luffy and the rest of the crew. Nami is depicted as an intelligent girl who is obsessed with obtaining money. She is able to use her three-sectioned staff and her climate skills to create powerful attacks; the most prominent of these staff weapons is the Klima-Tact, in which she manipulates the climate to create weather-based attacks.

Roronoa Zoro (ロロノア・ゾロ, Roronoa Zoro, spelled as "Roronoa Zolo" in some English adaptations), also known as "Pirate Hunter" Zoro, is a fictional character created by Japanese manga artist Eiichiro Oda who appears in the manga series and media franchise One Piece. He first appeared in the third chapter of the One Piece manga, published in the manga magazine Weekly Shōnen Jump in 1997. Zoro is the first crewmate to join Monkey D. Luffy to be part of his crew of pirates, after he is rescued by Luffy from execution. Zoro is a highly skilled swordsman and serves as the crew's combatant, though he possesses an extremely poor sense of direction which recurs as a running gag throughout the series. 

Born as a prince of Germa Kingdom, Vinsmoke Sanji is routinely ridiculed by his genetically enhanced siblings and is locked away by his father Judge for being a disgrace. With help from his sister Reiju, he escapes and flees Germa, a floating kingdom composed of several ships, after it enters the East Blue and his father permits it.

While serving as an apprentice cook on a passenger ship, nine-year-old Sanji stands up to a boarding party of pirates led by the infamous "Red Foot" Zeff. During the encounter, Sanji is swept into the sea by a massive wave. Zeff jumps in after him because of their common dream of finding the All Blue, a legendary area where the East, West, North, and South Blue seas meet, containing every kind of fish in the world. While castaways together, the pirate saves Sanji's life yet again by giving him all of their food. After their eventual rescue, Sanji stays with Zeff for several years and helps him build a floating restaurant, the Baratie. Zeff in turn makes him a first-rate cook and teaches him his kick-based fighting style. Mirroring Zeff, Sanji will never refuse a starving person a meal, and he uses only his legs when fighting to protect the hands he needs for cooking. He has a weakness for women and makes it a principle never to harm one, even if it means his death.

Eventually, he becomes infamous as "Black Leg" Sanji. While training for a period of two years in Emporio Ivankov's Kamabakka Queendom, he develops the Sky Walk, a variant of the Six Powers technique Moonwalk, which allows him to essentially run through air. Sanji receives his own Raid Suit from his family that grants him the ability to turn invisible, though he later destroys it out of fear of losing his humanity.

"God" Usopp is the sniper of the Straw Hat Pirates and one of the Senior Officers of the Straw Hat Grand Fleet. He is the fourth member of the crew and Athe third to join, doing so at the end of the Syrup Village Arc. Although he left the crew during the Water 7 Arc, he rejoined at the end of the Post-Enies Lobby Arc.

Usopp is the son of Yasopp and the late Banchina. He was born and raised in Syrup Village, serving as "captain" of the Usopp Pirates and being Kaya's close friend. After working with the Straw Hats to defeat Kuro and the Black Cat Pirates, he was invited to join the crew. Despite his usual cowardice, Usopp dreams of becoming a brave warrior of the sea just like his father and lives every day in pursuit of living up to this dream.

Tony Tony Chopper, also known as "Cotton Candy Lover" Chopper, is the doctor of the Straw Hat Pirates and one of the Senior Officers of the Straw Hat Grand Fleet. He is the sixth member of the crew and the fifth to join, doing so at the end of the Drum Island Arc. He was temporarily forced to join the Foxy Pirates during the Long Ring Long Land Arc but was quickly returned to Luffy's crew.

Chopper is a reindeer that ate the Hito Hito no Mi, a Devil Fruit that allows its user to transform into a human hybrid at will. He was taught medicine on Drum Island by his two parental figures, Doctors Hiriluk and Kureha. Chopper aims to travel all across the world in the hopes of accomplishing his dream of being able to cure any disease.

Nico Robin, also known by her epithet "Devil Child" and the "Light of the Revolution", is the archaeologist of the Straw Hat Pirates and one of the Senior Officers of the Straw Hat Grand Fleet. She is the seventh member of the crew and the sixth to join, doing so at the end of the Arabasta Arc. She temporarily left the crew during the Water 7 Arc but rejoined during the Enies Lobby Arc.

Born into a family of archaeologists, Robin is the daughter of Nico Olvia. Robin ate the Hana Hana no Mi at a young age, giving her the power to reproduce her body parts (or her entire body) on any surface at will. As the sole survivor of the destroyed West Blue island Ohara, she is currently one of only two people in the world known to have the ability to read and decipher Poneglyphs, a skill which is considered forbidden and threatening to the World Government.

She acted as the vice president of Baroque Works as "Miss All Sunday",[1] serving and partnering herself directly with the organization's president; the ex-Warlord: Crocodile, who operated under the codename "Mr. 0". She was a secondary antagonist of the Arabasta Saga, before joining the Straw Hats. Her dream is to find the Rio Poneglyph which tells the true history of the world, specifically the Void Century.

"Soul King" Brook is the musician of the Straw Hat Pirates, one of their two swordsmen, and one of the Senior Officers of the Straw Hat Grand Fleet. He is the ninth member of the crew and the eighth to join, doing so at the end of the Thriller Bark Arc.

Brook ate the Yomi Yomi no Mi, which allowed him to return to life after death once. Brook eventually learned to tap deeper into the powers of his Devil Fruit, giving him significant control over his own soul and the souls of others.

Originally a member of the Rumbar Pirates, he died and was resurrected through the power of the Yomi Yomi no Mi. However, due to the amount of time it took for his soul to find his body, it was reduced to a skeleton, keeping only his afro intact. Brook drifted alone in the Florian Triangle for 50 years, eventually meeting Luffy and serving as the Straw Hats' ally during the Thriller Bark Arc before officially joining the crew. His dream is to reunite with his old friend, Laboon, at Reverse Mountain, where he resides with Crocus.

"Iron Man" Franky is the shipwright of the Straw Hat Pirates and one of the Senior Officers of the Straw Hat Grand Fleet. He is the crew's eighth member and the seventh to join, doing so at the end of the Post-Enies Lobby Arc.

Born "Cutty Flam", he chose to go by his nickname of "Franky" until eventually permanently discarding his true name per the request of Iceburg to hide his identity. Originally from the South Blue, Franky was abandoned by his family as a 10-year-old, eventually making his way to Water 7. There, he came to be a member of Tom's Workers, until an incident resulted in his body being heavily damaged and requiring him to augment himself into a cyborg. Upon returning to Water 7, he became the leader of the Franky Family, a group of ship dismantlers and bounty hunters.

Franky and his followers were originally enemies of the Straw Hats at the beginning of the Water 7 Arc, until circumstances forced them to become allies at the end of the same arc and the Enies Lobby Arc. Due to this, he is the secondary antagonist of the first half of the Water 7 Arc. Franky's dream is to create a ship and circumnavigate the world with it, and he built the Thousand Sunny and joined the Straw Hat Pirates to fulfill his dream.

"Knight of the Sea" Jinbe is the helmsman of the Straw Hat Pirates and one of the Senior Officers of the Straw Hat Grand Fleet. He is the tenth member of the crew and the ninth to join, doing so during the Wano Country Arc.

Jinbe is a whale shark fish-man and a powerful master of Fish-Man Karate. His dream is to fulfill his former captain Fisher Tiger's dying wish of coexistence and equality between humans and fish-men. He was a member of the Sun Pirates, eventually becoming its second captain after the death of their original captain, Tiger. He eventually became one of the Seven Warlords of the Sea, though he resigned during the Summit War of Marineford. Vegapunk later cloned Jinbe as one of the Seraphim, S-Shark, to replace the Warlords.

Prior to and amidst said war, Jinbe befriended Monkey D. Luffy, and two years later allied with him and his crew to prevent the New Fish-Man Pirates' coup d'état against the Ryugu Kingdom's Neptune Royal Family. Luffy thereafter invited him to join the Straw Hat Pirates, but Jinbe held it off until severing ties with Big Mom during the Whole Cake Island Arc. After staying behind in Totto Land to protect the Sun Pirates from Big Mom's wrath, Jinbe returned to the Straw Hats during the Wano Country Arc, officially announcing his status as a member of the crew.