Brook

Brook is the musician of the Straw Hat Pirates. He is a skeleton the Straw Hats found on board a ghost ship after drifting into the Florian Triangle. He is a Devil Fruit user who ate the Yomi Yomi no Mi and is an undead being brought back into a pseudo-immortal state because of its powers. He is the ninth member of the Straw Hat crew and the eighth to join Luffy's crew. He is also one of the two swordsmen onboard their current ship with the other being Zoro. He fills the role of the long awaited musician that Luffy wanted for his crew since his journey began.

Appearance
Brook is an extremely tall skeleton dressed in formal attire complete with top hat and cane. At 8' 8.5" in height, he is the tallest member of the Straw Hat crew. Despite having no skin, he still has an afro which he says is because his hair has very deep roots. Brook's style is that of a gentleman consisting of a coat, top hat, pants, and afro which are black while the inner linings of his coat are yellow-orange. The ribbon tied in between his coat and around his neck is blue. The outer covering of Brook's cane sword which he carries is purple. Also, due to his many years of seclusion his clothes have become somewhat tattered.

After two years, however, he has changed to more colorful and high-end clothes, as though to represent a rock star. He has heart-shaped sunglasses, a yellow feather boa, a top hat with a giant crown on the brim and orange pants with a pink floral design.

Before his death, Brook was a tall, skinny man with a rather distinctive face. He had a slight goatee on his chin and some side burns. He typically wore shades. On his forehead was a scar that slightly resembles a diagonal omega sign (Ω). This scar was retained in his skeleton state as a distinctive crack across his skull. Brook's facial appearance, accompanied with his style of clothing, resembles a type of appearance that is commonly associated with various music artists such as Ozzy Osbourne, Slash, and other musical celebrities with similar features.

According to Oda Eiichiro, the colours that represent Brook are black and white, he resembles a horse and he smells of tea.

source: onepiece.wikia.com

Franky

Franky (フランキー) is the shipwright for the Straw Hat Pirates. He is a 36 year old cyborg from Water 7 and was introduced in the story as the leader of the Franky Family, a group of ship dismantlers. He was originally named Cutty Flam until he threw away his original name for his nickname per the request by Iceburg to hide his identity. Franky and his followers were originally introduced as antagonists of the Water 7 Arc against the Straw Hats until circumstances forced them to become allies. Per the request of the Franky Family, Franky was allowed to join the Straw Hats to fulfill his dream. He is the eighth member of the Straw Hat crew and the seventh to join Luffy's crew. He is also the second member to have been a former antagonist (the first being Nico Robin).

Appearance
As a direct result of his modifications that he's conducted upon himself as well as years having spent as a ship dismantler, bounty hunter, and street thug in Water 7, Franky is a powerfully built man with a height of at least seven feet, and he is the second tallest member of the Straw Hats. His forearms are relatively enormous while his biceps are comparably small. He has brightly-colored blue hair and blue star tattoos on his forearms. His choice of clothing usually comprises of a speedo, which causes people to call him a pervert, and an open loud Hawaiian shirt that has a large golden chain necklace around his neck. During the Straw Hats separation, after blowing up Vegapunk's laboratory, the skin gets burned off Franky's face. He also has a pair of sunglasses which he usually wears when things start to get serious.

According to Eiichirō Oda, Franky most resembles a bull, he is represented by the color light blue (cyan), and he smells of cola.

After the two year time-skip, Franky is first seen to have a hair in the style of a buzz cut, and later on, he reveals that his hair is now controllable and can change different styles instantly by pushing down on his nose for more than three seconds. He also has two stitch-mark scars on his torso running down from his the back of his neck indicating that he had sewn his skin back on, making it seem more than likely that he has finally fashioned his metal 'endoskeleton' to wrap around his entire body, and not just his visible front (since the initial operation to become BF-36 was done by himself, he could not do work on his own backside). His shoulders, torso, and arms are also much bigger than before, and with studded hands that look almost robotic in appearance, but he also revealed that inside of his huge arms he still has his real normal-sized hands. He now appears to be wearing metal rigged suspenders. He has replaced his elbows with large, light blue hinges, his shoulders with a large red ball and socket joint with 'BF-37' labeled on them, and his forearms with large, light blue cubes, with his trademark star retattooed being split by an edge. These new features house upgrades he gave himself during the last two years, but their true potential and ability has yet to be fully shown.

source: onepiece.wikia.com

Nico Robin

Nico Robin is the archaeologist of the Straw Hat Pirates. She was originally introduced as the Vice President of Baroque Works known as Miss All Sunday before joining up with the Straw Hats. She is the seventh member of the crew, the sixth to join, and the second to rejoin, doing so during the Enies Lobby story arc. She was also the first member to have been a former antagonist. She ate the Hana Hana no Mi. During the Post-War arc, she became involved with the Revolutionaries for two years. Her dream is to find the Rio Poneglyph which tells the True History.

Appearance
Nico Robin is a tall, slender yet athletic woman with shoulder length black hair. Her eyes are blue in the anime with dark and wide pupils (brown eyes in the manga and the 10th movie), and she has a very characteristic plain nose. Robin's limbs are somewhat long, especially her legs, contributing greatly to both her fighting capabilities (given the nature of her powers) and overall height, and like most female characters in the series, she has a narrow waist. Many people consider her attractive. Robin is probably the most complex dresser next to Nami.

She has no trademark look like the others, though her all purple cowgirl look from when she was first introduced is often associated as her trademark look. She frequently wears somewhat revealing clothing that is either dark in color (often black or purple) or consisting of leather, sometimes both. She seems to be fond of revealing outfits and high heels. Both Robin and Nami wear high heels and revealing outfits, and, like Nami, the high heels don't affect Robin's height, posture, or the way, or speed at which she walks.

Robin sometimes wears a gold arm band with white strings attached to it and the letter N on it, which stands for her family name, and also had a similar one with BW on it, which stood for Baroque Works, but she no longer wears it as she is no longer affiliated with the group; she has also worn a cowgirl hat on numerous occasions. In the anime, Robin's skin tone is slightly darker unlike in manga coloured artworks where it is lighter. Robin also resembles her mother greatly, with the exception of her hair color and style as well as having slightly darker skin tone than her.

In the Alabasta Arc, she wore a skimpy cowgirl outfit consisting of a purple cleavage-exposing top and matching miniskirt, both with white ornaments hanging from them, and a white fur-lined coat paired with a white cowboy hat and white high-heeled boots.

In the Skypiea Arc, she still wore her trademark white cowboy hat, along with a yellow sleeveless shirt and purple pants reaching to her calves, with a simple belt around her waist, and purple high-heeled sandals. She sported her white ornament on her left arm.

In the Water 7/Enies Lobby Arc, she wore a short, cleavage-revealing leather dress with long sleeves over what looked like a lighter, white polka-dotted under dress. She also wore black thigh high-heeled boots.

In the Post-Enies Lobby Arc, she was seen wearing a tight-fitting, red t-shirt that has the Galley-La emblem at the front and a pair of black trousers. She also wore a pair of white high-heeled shoes. Later, she replaced the t-shirt with a tight, pinstriped purple buttoned sweater and dark high-heeled shoes.

In the Thriller Bark Arc, she wore a short purple dress with lace embroidered edges, stockings reaching up to her thighs held up by suspenders, and black high-heeled boots with two lines of buttons on the front.

In the Spa Island Arc, Robin was seen wearing a white bikini top with pink straps and ruffles lined at the base of her front. She also had a yellow towel draped around her waist.

In the Sabaody Archipelago Arc, she wore a black (purple in the anime) outfit consisting of a cowboy hat, a cleavage-revealing sleeveless shirt, with a wide, yellow collar covered with black concentric circle motifs, matching pants reaching down to her calves, and high-heeled shoes. She also had a string of round and yellow ornaments that hung loosely from around her waist.

While imprisoned at Tequila Wolf, Robin wore a single-piece blue prison jumpsuit, which was left open to reveal her bosom, and had her hands restrained with chain-linked Kairoseki handcuffs.

After the two year time-skip, Robin's hair goes past her shoulders and is pulled back, revealing more of her forehead. Her outfit after the timeskip now consists of a long pink sari-like skirt with a partially-zipped purple leather vest with a V neck line similar to Boa Hancock's, sunglasses, pink high heeled pumps, and a pink backpack. And like Nami, her breasts have gotten larger.

The author has also replied to a fan's question to saying that right now Robin's measurements are as follows:

* Height: 188 cm (6'2"), making her the third tallest member of the Straw Hat Pirates.
* Her 3 measurements are (according to Sanji and series creator Oda in supplemental material) B99-W59-H89 (38"-23"-36"), making her breasts an I-cup in Japan.

According to Oda, Robin most resembles a crane, is represented by the color purple, and she smells of flowers.
Apparently the flower that best represents her is the Cassablanca.

source: onepiece.wikia.com

Tony Tony Chopper

Tony Tony Chopper is the doctor of the Straw Hat Pirates. Chopper is a reindeer that consumed the Devil fruit, Hito Hito no Mi. He comes from Drum Island, which makes him the only member of the Straw Hat Pirate Crew who was born on the Grand Line. He is the sixth member of the crew and the fifth to join, as well as being the youngest member on board. He ate the Hito Hito no Mi, or the 'Human-Human Fruit' when translated.

Appearance
Most of the time, Chopper is a toddler-sized human/reindeer hybrid, but his Devil Fruit abilities allow him to change his appearance depending on the situation. Chopper's left antler has a metal plate wrapped around it at all times, from being broken in a fight when he was younger. The usual clothing he wears includes a pale red/pink, fuzzy top hat with a sideways medical cross (given to him by Hiluluk) and a maroon pair of shorts. He also sometimes wears a blue backpack that has the same sideways medical cross as his hat. Chopper also has a remarkable feature that no other reindeer have, a blue nose, while normal reindeers have black ones. As Oda's style evolved, Chopper has been given a more "chibi" appearance, meaning that when in his Brain Point, Chopper has a larger head and eyes.

Chopper wears different outfits just as any other character in the crew.

In Alabasta, he wore a shirt with a green-lined collar, then a bigger one with giant sleeves that is light blue with dark blue liners.

At Enies Lobby, he wore a red leather jacket.

A running gag is that various characters in One Piece think Chopper is a tanuki (raccoon-dog, often simply translated as "raccoon") whilst in his Brain Point form. This is a play on the similar word "tonakai," the Japanese word for reindeer, from which the "Tony" in Chopper's name is derived. His heavy point form likewise is mistaken for a gorilla or an abominable snowman.

Many female characters, such as Nami, Robin, and Porche, find Chopper very cute.

Oda has stated that he uses the color pink to represent Chopper, he enjoys spring on a winter island, his favourite foods involve cotton candy, chocolate and other sweet food and drinks, he would be the youngest son, if he were real his nationality would be Canadian, and (Oda was answering the questions as Chopper) for his smell it would be sugar and medical supplies. The flower that best suits Chopper is the tulip.

After the two-year time skip, Chopper wears a new blue and pink cap about the same size as his old pink hat. The X has a white circle surrounding it, and a ring of dots around the circle, while the cap has buckles hanging from it. He also wears a white and yellow vertical-striped tank top and a orange pair of shorts. Chopper's Brain Point form has changed little, aside from being slightly slimmer. His Walk Point form has grown considerably, now being roughly as tall as Usopp. His horns are larger, he has more muscle, and his fur is longer. His Heavy Point has not been shown. He was recently shown to have developed a new form during the timeskip, Kung Fu Point, which he used to defeat King Neptune's soldiers.

source: onepiece.wikia.com

Sanji

Sanji is a pirate and the chef of the Straw Hat Pirates. He is the fifth member of the crew and the fourth to join. Since he was born in North Blue, he is the first Straw Hat not to originate from East Blue. Being labeled as one of the "Monster Trio," he's one of the top three fighters in the crew. His dream is to find the rumoured All Blue which is where East Blue, West Blue, North Blue, and South Blue meet along with their wildlife.

Appearance
Sanji is a slim, long-legged, young man with blond hair, often well-dressed, and keeps his hair brushed over one side of his face. For the initial part of the series, this was the left side. Due to his left eye never being seen, many fans have questioned whether he has one at all. In the manga it was usually covered one way or another, but is seen in the anime (episodes 21, 27, 82, 128 and Movie 6 although usually very briefly and most likely due to animation errors). Later, after the two year time skip, he switched his hairstyle so that it covers the right side.

Among Sanji's physical traits are his distinctive eyebrows. Both form a spiral but at different ends. His right eyebrow forms a spiral at the outer end, while his left eyebrow forms a spiral at the inner end. This means his face is asymmetrical with the position of his eyebrow spirals. This, however, is not fully seen due to his hairstyle. He still gets very upset if somebody, typically Zoro, mocks him over the spirals.Though, on rare occasions, Sanji's other eye was seen in the anime, the spiral was never witnessed.

Sanji almost always wears a black, double-breasted suit with a tie and long-sleeved, buttoned shirts of varying colors, usually orange, blue or black, with or without pinstripes. His fashion changes at times, like in the Water 7 Arc where he had no suit jacket, but a black vest over an orange, pinstriped shirt. Also in the Skypiea Arc, he wears a pink dotted shirt with black knee-length pants He also wears dress shoes, mostly for his Black Leg martial arts. These shoes are extremely durable, and were designed to increase the power of his attacks, though he can attack sufficiently without them as he did against Kuroobi. Sanji is also a chain-smoker, and is rarely seen without a cigarette. During the Straw Hats' separation, Sanji is coerced into dressing as a typical okama, complete with a wig and heavy makeup, though reverts to his usual outfit and appearance sometime after. He may also wear orange sunglasses, as seen in the Alabasta arc.

On the thumb of his right hand, Sanji has three small scars from when he cut himself peeling apples.

After the 2 year time-skip, Sanji now covers his right eye, shows his left eye, and has grown his hair just slightly longer. He also sports a dark goatee, and stubble on his upper lip. Both his left and right eyebrow are curled to the right. He wears a black and yellow 3-piece suit.

According to Oda, Sanji most resembles a duck, is identified by the color blue, and smells of seafood and cigarette smoke.

source: onepiece.wikia.com

Usopp

Usopp (ウソップ) was born in Syrup Village. He is the sniper of the Straw Hat Pirates. When Usopp was first introduced, he was often (comically) labeled as the "Liar" of the Straw Hat Pirates. He is the fourth member of the crew, the third to join, and also the third to rejoin at the end of the Post-Enies Lobby Arc. He is known with a bounty on his head by his alias and alter-ego "Sogeking".

Appearance
For most of the story, Usopp is a tanned, slim teenager with black curly hair and a long nose, which is apparently an allusion to Pinocchio, a wooden boy from a story of the same name who possessed a nose that would stretch after he lied. He usually wears a dark yellow plaid bandanna, a blue and white striped armband on his left arm, special sniper goggles (he also has a pair of clear rectangular goggles that he sometimes wears in situations where he doesn't have his sniper goggles, like when he first met the Straw Hats or when his sniper goggles were stolen by Mr. 2), brown overalls with a white sash and no shirt underneath (although he wore a murky green shirt during the Skypiea Arc). He also carries with him a yellow satchel, which he stores all his tools and gadgets in. Usopp inherited his famous nose from his mother, while the rest of his face closely resembles his father's. During the Straw Hat separation, after landing in the Forest of Gluttony, Usopp grew quite fat.

After the two year timeskip, Usopp, no longer fat, has grown his hair longer. He has also gained more muscle and grown "manlier", being slightly taller and more muscular than before. Usopp now has a new pair of goggles around his neck (his sniper goggles weren't shown) and has some headphones or ear protectors on. He also now has a little goatee along with a new white suncap he wears on his head. He also has a new pair of rolled-up yellow pants with red suspenders, and a pair of boots. His trademark yellow satchel has been replaced with a red one, but he still has his blue and white striped wrist band on his left arm.

Oda claims that Usopp is most represented by the armadillo. Oda has also said that he uses the color yellow to represent Usopp, and that he smells of gunpowder.

source: onepiece.wikia.com

Nami

Nami is a pirate and the navigator of the Straw Hat Pirates. She is officially the third member of the crew after defeating Arlong, and the second to join. She briefly betrays the crew during the Baratie Arc and rejoins at the end of the Arlong Arc after her past and true intentions are revealed.

Appearance
Nami is a young , somewhat tall girl with a slim build, and originally had short orange hair. She was the first main character to appear in Episode 1 before Luffy. Many people consider her to be very good looking or even beautiful. She has a blue tattoo (black in the manga) on her left shoulder which represents mikan and pinwheels (a homage to both Bellemere and Genzo, respectively), where she used to have a tattoo for being a member of Arlong's crew.

Nami wears a variety of clothes in the series but her longest lasting outfit is a white and blue striped shirt, an orange mini-skirt and orange high-heeled boots. Nami wears high heels sandals or boots in every arc, but her height and posture are not usually affected by the height of her heels. Nami doesn't walk like a regular person in heels, instead she runs while wearing them. She retains her original look until the end of the Captain Kuro Arc, after which she is seen wearing a different outfit for each arc. During the Arlong arc, Nami wore a green cami and her orange high heel sandals; thereafter, Nami wore strappy, high heeled sandals and more revealing outfits (with the tattoo no longer being a secret). Nami wore a blue bikini, maroon pants, and orange high heel sandals for the Skypiea arc. In the city of Water 7, she wore a maroon cami, a white mini-skirt, and orange high heel sandals. Then she changed to black high heel gladiator sandals during the Enies Lobby arc, along with a brown clevage-revealing jacket and a blue mini-skirt. While on Thriller Bark, she wore a pink blouse, a brown skirt, and brown high heel boots. She later wore a wedding dress and white high heel pumps with her dress. She seemed to have abandoned the sandals for high-heeled boots as of Chapter 435 but she started using sandals again at the end of Thriller Bark arc. She usually pairs her tops with skirts that have rings on them. For the Sabaody Archipelago Arc, Nami wore a orange shirt, white short shorts, and high heel sandals. Nami's clothes consisted of a pink shirt, short jean shorts, and high heels for the Straw Hat Separation Arc.

Her overall physique matured suddenly (though this is, most likely, a simple change in style of artwork). Her fashion frequently changes as does her hair style. Many of her shirts feature four-letter words, such as "MODE", "GOLD", or "EVIL", similar to a shirt that Bellemere once wore that had "MACE" on it. On her left arm she wears the Log Pose, which she needs in order to be the navigator of the ship, and a yellow bracelet, given to her by her sister, Nojiko. She was also seen wearing glasses during the Skypiea arc.

In SBS Volume 6, Oda said, according to Sanji, her measurements were 86-57-86 cm = 34-22-34". The author has also replied to a fan's question saying that right now Nami's measurements are as follows:

* Height: 169 cm = 5'6½"
* Measurements (B-W-H): 95-55-85 cm = 37-21-33"

He specified in a later SBS that Nami's under-bust size is 65 cm, making her breasts an I-cup in Japan, or an F-cup in the US. However, her breasts seem to grow into and then "reset" throughout the arcs (this is much more obvious in the manga and in one of the movies). Oda has also said that Nami resembles a cat, that the color orange represents her, and that she smells of mikan and money.

After the two year timeskip, Nami's hair has grown rather long, reaching down to her lower back. Her breasts have also grown larger and rounder, like Robin's, but apart from this her appearance has not changed much, save for the fact that both her body curves and hour-glass figure have become more pronounced. She also appears to have grown taller, as she appears to be just slightly shorter than Robin now (although they are both wearing high heels). Her outfit after the timeskip consists of a revealing green and white bikini halter top, low-rider jeans (that expose some of her hips), orange high-heeled sandals, and a pair of pearl-like earrings.

source: onepiece.wikia.com

Roronoa Zoro

Roronoa Zoro (ロロノア・ ゾロ) is a pirate, former bounty hunter, and one of the main protagonists of One Piece. He was the first member to join the Straw Hat Pirates, and to date is considered the largest threat and most dangerous member in the crew after Luffy. He is famed as a master swordsman, user of the Santoryu style, and his great strength (and the actions of his captain) sometimes leads others to believe he must be the true captain. Being labeled as one of the "Monster Trio", he's one of the top three fighters in the crew. His dream is to become the greatest swordsman in the world. Zoro was labeled as one of "The Eleven Supernovas", the eleven rookie pirates with bounties over 100,000,000 Beli to have reached the Red Line. Zoro's current bounty is 120,000,000 Beli.

Appearance
Zoro is an average sized, muscular young man. He almost always carries around his three swords, bundled up with a green haramaki over his right hip, allowing him to easily draw them with his left hand. His right hand is usually seen resting over them, though he can also use this hand to pull his swords out before sitting down. He has three identical gold earrings on his left earlobe. Zoro normally keeps a black bandanna tied around his left arm. He ties the bandanna around his head when he is fighting seriously against an opponent.

Zoro's shirt varies from time to time, but he consistently wears black trousers tucked inside black boots. Zoro is most commonly seen wearing a plain white shirt with three buttons at the collar, but after this shirt is effectively torn to shreds due to the incident at Thriller Bark, he wears a different shirt with each arc.

His body is covered with scars from his many battles, most notably the one acquired during the Baratie Arc, when he lost a duel with the world's greatest swordsman, Dracule Mihawk. As a result, Zoro was left with a massive scar stretching from his left shoulder to his right hip. In the Little Garden Arc, he tried to free himself from a wax prison by cutting off his feet. Although he did not entirely succeed, he gave himself a scar around each ankle. These scars are marked by black stitches.

Zoro's other remarkable feature is his cropped green hair, which Sanji often teases him about by calling him "marimo" (moss-ball, moss-head in the Viz Manga and FUNimation dub).

After the two year timeskip, Zoro has a new scar running down his left eye, which is now implied to be blind as it is almost always closed. His neck appears much thicker and more muscular and his hair became slightly longer. Zoro now wears a long, open dark-green coat, closed on his waist by a red sash, in which his swords are now tucked, and his black bandana tied around the left sleeve. He has no shirt underneath, and his green haramaki is visible under the coat. Zoro has also gained more muscle. He also appears to have gotten taller, as he was several inches taller than Nami when standing near her.

According to Oda, Zoro resembles a shark. Oda uses the color green to represent Zoro, he smells of steel, and the flower that suits him best is the thistle.

source: onepiece.wikia.com

Monkey D. Luffy

Monkey D. Luffy (モンキー･D･ルフィ) is a pirate and the main protagonist of One Piece. He is the son of the Revolutionary Army's commander, Dragon, grandson of the famed Marine, Garp, and the foster brother of the late "Fire Fist" Portgas D. Ace and Sabo. His life long goal is to become the Pirate King by finding the legendary treasure left behind by the Pirate King, Gol D. Roger. He believes that being Pirate King means you have the most freedom in the world.

As the founder and captain of the Straw Hat Pirates, he is the first member that makes up the crew as well as one of its top three fighters, the "Monster Trio". Luffy was one of eleven rookie pirates who had been referred to as "Eleven Supernovas", the eleven pirates with bounties over 100,000,000 Beli to have reached the Red Line. Luffy's current bounty is 400,000,000 Beli stated by the "impostor Luffy" after the time skip, and confirmed by one of the readings from a Pacifista.

He has a worldwide reputation for causing trouble, even among the Shichibukai, and the Marines, committing actions that were deemed dangerous by the World Government. Luffy has repeatedly committed crimes against the World Government.

He has gained a reputation for being 'reckless' and, in some cases, 'insane', after causing an incident in Enies Lobby, entering and escaping Impel Down, and joining the Battle of Marineford. He is therefore famous for being the only pirate to not only break into the 3 most important government facilities, but also for being the only one to escape all of them alive.

This, plus the fact that he punched out a Tenryubito with full knowledge of the consequences and his heritage has caused Luffy to be labeled as a "dangerous future element". He has eaten the Gomu Gomu no Mi.

Appearance
Luffy is renowned for wearing his trademark straw hat (from which he gets his nickname "Straw Hat Luffy") which was lent to him when he was young by the legendary pirate captain, "Red-Haired" Shanks, who in turn received it from Gol D. Roger. His outfit somewhat mimics Shanks' own outfit in that he wears short trousers (although his are much shorter than Shanks') along with sandals and a vest. Luffy also has a scar with two stitches underneath his left eye (he got it in Chapter 1) and short black hair. He was severely wounded by Akainu in the Whitebeard War, leaving a large X-shaped scar on his chest. Appearing to be scrawny underneath his shirt, he has a surprisingly well built physique. Pre-timeskip he was very short, dwarfed by most characters in the series.

Luffy, for the most part, has the same outfit throughout most of the series, as opposed to the rest of the crew, who change frequently. Luffy may wear a different outfit to suit the climate of an island (like a hooded parka on Drum Island or desert robes in Alabasta), but will switch back to his trademark vest and shorts after the adventures on that island are over.

Though Luffy prominently wears a red vest and blue shorts, he will wear his usual outfit in different colors. For example, in Enies Lobby he wore black shorts because they had pockets in which he could carry meat, on Thriller Bark he wore an orange vest and red shorts, and on Sabaody Archipelago he wore a blue vest and dark blue shorts. During the break-in at Impel Down Luffy was shown wearing a light blue vest with red shorts and after the fight between Magellan and Luffy, Inazuma gave him a yellow vest. He does, however, no matter where he is, wear his Straw Hat through absolutely everything, though at the start, the hat was prone to getting knocked off his head easily, forcing Luffy to either put it aside or have someone hold onto it during fights, he has since gotten a string strap for it which was sewed on by Nami, allowing the hat to hang from his neck during fights.

Luffy has been known to sport other miscellaneous items on his person from time to time. During the Skypeia Arc, he was seen wearing a black wristband around his left wrist with a white bangle over it, and after the battle against Moria in Thriller Bark, Luffy wore a decorated dark armband around his left bicep. This armband was later revealed to be a map that leads to Captain John's lost treasure, which Buggy sought for some time - leading to Luffy handing the armband in for Buggy in exchange for his services at helping him navigate through Impel Down.

During his return to Marineford to give a silent prayer, Luffy was briefly shown with four characters written on his right arm spelling 3D2Y, with the 3D crossed out to symbolize that the Straw Hat Pirates should meet up in 2 years (2Y) rather than the 3 days (3D) as planned after fleeing from Bartholomew Kuma.

After those two years, Luffy wears a long-sleeved red cardigan with a yellow sash tied around his waist, somewhat reminiscent of Gol D. Roger's outfit. His hair is only slightly longer and it also appears that Luffy has grown, as he seems to be only slightly shorter than Hancock.

source: onepiece.wikia.com

One Piece

One Piece
One Piece (glossed in print as ひとつなぎの大秘宝), Hitotsunagi no Daihihō, "The Great Treasure of One Piece", but still pronounced Wanpīsu) is a legendary treasure said to be of unimaginable value.

It is said that it was hidden somewhere deep in the Grand Line, presumably in the last island Raftel, by its previous owner, the Pirate King Gol D. Roger.

The Mystery of the Great Treasure

Aside from the Roger Pirates and Whitebeard before his death, no one, save for possibly his crew actually knows what the great treasure is.

Given the recurring theme of treasure being something of great personal value (for example Luffy's hat), One Piece may simply be an item that Gol D. Roger valued. In Buggy's flashback to his days as a member of the Roger Pirates, he discussed with Shanks the meaning of a treasure, and he found that all the crew shared the same views regarding personal value.

The closest the Straw Hat Pirates have ever come to finding out the nature of One Piece was during the Sabaody Archipelago Arcwhen tried to ask Silvers Rayleigh about it. However, Luffy stopped Usopp from discussing the treasure on the grounds that it would defeat the purpose of their adventures, and that becoming the Pirate King would have little merit if he already knew about One Piece.

After constant speculations and doubts, the existence of the treasure was seemingly confirmed by Whitebeard with his last breath. He mentioned that "all of it will be written into history" and "a grand battle that engulfs the entire world" will come when One Piece is found.

source: onepiece.wikia.com

The Pirate King

The Pirate King (海賊王) (called King of the Pirates in the English versions) is the strongest pirate alive and owner of the legendary treasure that was later dubbed as "One Piece".

The term "Pirate King" was originally a simple nickname for Gol D. Roger to distinguish himself among swashbucklers. Upon Roger's execution, the name was romanticized by the people of the One Piece world into an actual title, much in the same way One Piece itself was simply "Roger's treasure" until the Pirate King's death. In the English manga and anime, "Pirate King" clearly marks this distinguishment; although Gol D. Roger was Pirate King, Monkey D. Luffy seeks to become the new Pirate King 22 years later.

Before his death, Pirate King Gol D. Roger hid One Piece. It was rumored to be located at Raftel, the island at the end of the Grand Line. The frenzy over discovering and owning such a massive treasure sparked the "Great Age of Pirates". Until One Piece has been claimed, there will be no current Pirate King.

Until his death, the closest person to becoming the Pirate King was Whitebeard (Edward Newgate). Many people who had met Luffy, such as Coby and Helmeppo, believe that he will be the Pirate King ; Kokoro also addressed Luffy as the Pirate King[4] and Shakuyaku has stated that both she and Silvers Rayleigh were rooting for Luffy to achieve this goal.

The reasons for a person wanting to be the Pirate King vary, people like Blackbeard and Gekko Moriah wish to have it for the power and influence the title would come with, while others like the Yonkou are considered candidates for it because they're extremely powerful and very close to it, but the two shown so far appear to not have any interest in it. And still others like Luffy and Crocodile (prior to the event that caused him to let go of it) wish to become the Pirate King because it is a dream of theirs. Luffy (and Crocodile in his youth) seem to want it for the adventures that are involved with becoming the Pirate King. The Pirate King is said to be the ruler of the sea (Enel asks Luffy about the country the Pirate King rules [after Luffy says that he will be one], Luffy answers this by saying that the Pirate King is the king of the sea, Enel then says that it would be a very interesting title). When talking to Silvers Rayleigh, Luffy said that the Pirate King is the person with the most freedom on the sea.

source: onepiece.wikia.com