The Kamehameha is the first energy attack shown in the Dragon Ball series. The Kamehameha is the most widely used finishing attack in the Dragon Ball series, and is Goku's signature technique. It is also a signature attack of the students of the Turtle School.
Akira Toriyama actually tried a number of poses when he was alone in order to decide the best pose for the Kamehameha. After much contemplation, he could not decide on a name for his "Kame" attack, so he asked his wife (Nachi Mikami), who came up with the name.[12] She told Akira that it would be easy to remember the name of the attack if he used the name of the cultural Hawaiian king named Kamehameha (lit. "the very lonely one" or "the one set apart" in Hawaiian language).
The Kamehameha is formed when cupped hands are drawn to the user's side and ki is concentrated into a single point (between their cupped hands). The hands are then thrust forward to shoot out a streaming, powerful beam of energy. The blast can also be used, generally under extenuating circumstances, with just one arm or even the feet. In most variants, the user utters the word "Ka-me-ha-me-HA!!!" as they charge and release the attack. Master Roshi's Kamehameha is called the Original Kamehameha in the Budokai Tenkaichi series, and requires some time to charge.
The Kamehameha was invented by Master Roshi by practicing for fifty years spanning pre-Dragon Ball. By drawing his latent ki into the palms of his hands, Roshi is able to expel an explosive beam of ki energy. Goku learns it after witnessing Master Roshi unleashing the blast to extinguish the flames at Ox-King's home on Fire Mountain. To Roshi's surprise, Goku successfully performs the technique on his first attempt, although it is only strong enough to destroy the car that Yamcha gave to Bulma earlier. It was also learned by Krillin and Yamcha, who use it during the 22nd World Martial Arts Tournament against Chiaotzu and Tien Shinhan respectively. Tien Shinhan also easily copied it during the tournament after having it used against him. After the Turtle School students learn the attack, they teach it to others, and the attack becomes a very popular one to use during battle. Cell is also capable of using it due to the cells of Kamehameha users within his design. Majin Buu learns the technique after seeing Goku perform it during the Majin Buu Saga.
The Kamehameha has several different colors in the anime, movies, video games, and manga. The power and concentration of the different types of Kamehameha also vary greatly. Whitish blue is its standard and original color. In some episodes of Dragon Ball Z and some video games, the color of Goku's Kamehameha color is yellow instead of the primary blue color and Gohan's Electric Kamehameha in his ultimate form is also yellow. When Goku is in his Super Saiyan 4 form, his 10x Kamehameha is red-colored. Majuub's Chocolate Kamehameha has a pink color (but is blue in its debut). Majin Buu's various forms can also use the Super Kamehameha, which also has a pink color or the original blue color.
Because the Kamehameha has expanded to the arsenal of heroes, allies, and even villains, it has been personalized by few; something mostly done by characters who did not graduate Roshi's Turtle School (like Tien Shinhan for example). In their battle against Bio-Broly, both Trunks and Goten use the attack; however, Trunks extends both arms to sides and begins charging the attack, and after saying the incantation, he throws his hands forth and fires a blue energy blast with Goten's Kamehameha. During the Namek Saga, Krillin also uses a different stance on different occasions, normally alongside Gohan's Masenko; with one hand behind the other, Krillin says the incantation and unleashes the Kamehameha Wave. Based on these personalized variations and others, it is possible that the incantation is the only preparation required to produce the wave.
In the live-action film adaptation Dragonball Evolution, the technique is quite similar to the Kamehameha used in the anime and manga, however with very few differences depending on the user: Roshi has to channel ki from his chest to his arms before he releases it through his hands while Goku has to channel ki outside of him forming an aura as he crosses his arms in an X shape while the rest of the technique is similar to how Goku usually uses it. Also, unlike the anime, it has more uses than the typical Kamehameha, it can light torches as well as be used as a defibrillator (the latter demonstrated by Roshi saving Goku from near death after Mai shoots him). The more concentration put into it will make the Kamehameha stronger (such as when Goku combines his normal form with Oozaru form into the attack and forms the Kamehameha into a traditional beam rather than a small flow of energy).
Goku also uses the Kamehameha as his Ultimate Attack in the video game based on the movie.
