James Francis Cameron (born August 16, 1954) is a Canadian filmmaker and deep-sea explorer. A major figure in the post-New Hollywood era, his films combine cutting-edge film technology with classical filmmaking techniques and have grossed over $8 billion worldwide, making him the second-highest-grossing film director of all time. Cameron has received numerous accolades including three Academy Awards, two Primetime Emmy Awards, and four Golden Globe Awards, as well as nominations for six British Academy Film Awards.

Born and raised in Canada, Cameron moved to California aged 17 and enrolled at Fullerton College, and then studied at the USC library. Beginning his career with the short film Xenogenesis (1978), he first gained recognition for writing and directing the science fiction action film The Terminator (1984). He had further success with Aliens (1986), The Abyss (1989), Terminator 2: Judgment Day (1991), and True Lies (1994), as well as the Avatar franchise (2009–present). He directed, wrote, co-produced, and co-edited the historical romance epic Titanic (1997), winning Academy Awards for Best Picture, Best Director, and Best Film Editing.

Three of Cameron's films—Avatar (2009), Avatar: The Way of Water (2022) and Titanic (1997)—are amongst the top four highest-grossing films of all time, with Avatar in the top spot until it was surpassed by Avengers: Endgame (2019), but it has returned to first place since 2021. He directed the first film to gross over $1 billion, the first two films to gross over $2 billion each, and is the only director to have had three films gross over $2 billion each. The Terminator, Terminator 2: Judgment Day, and Titanic have been selected for preservation in the National Film Registry by the Library of Congress. Cameron also co-founded the production companies Lightstorm Entertainment, Digital Domain, and Earthship Productions. In 2010, Time named Cameron one of the 100 most influential people in the world.

In addition to filmmaking, he is a National Geographic explorer-in-residence and has produced many documentaries on deep-ocean exploration, including Ghosts of the Abyss (2003) and Aliens of the Deep (2005). Cameron has also contributed to underwater filming and remote vehicle technologies, and helped create the new digital 3D Fusion Camera System. In 2012, he became the first person to complete a solo descent to the bottom of the Mariana Trench, the deepest part of Earth's ocean, in the Deepsea Challenger submersible. He is also an environmentalist and runs several sustainability businesses.

James Francis Cameron was born on August 16, 1954, in Kapuskasing, Ontario, to Philip Cameron, an electrical engineer, and Shirley (née Lowe), an artist and nurse. He is the first of five children, with two brothers and two sisters. His paternal great-great-great-grandfather emigrated from Balquhidder, Scotland, in 1825. Cameron spent summers on his grandfather's farm in southern Ontario. He attended Stamford Collegiate in Niagara Falls. At age 17, Cameron and his family moved from Chippawa to Brea, California. He attended Sonora High School and then moved to Brea Olinda High School. Classmates recalled that he was not a sportsman but instead enjoyed building things that "either went up into the air or into the deep".

After high school, Cameron enrolled at Fullerton College, a community college, in 1973 to study physics. He switched subjects to English, but left the college at the end of 1974. Cameron worked odd jobs, including as a truck driver and a high school janitor. He drank beer, frequently consumed cannabis and LSD, and wrote in his free time. During this period, he learned about special effects by reading other students' work on "optical printing, or front screen projection, or dye transfers, anything that related to film technology" at the USC library. After the excitement of seeing Star Wars in 1977, Cameron quit his job as a truck driver to enter the film industry.

Cameron's directing career began in 1978. After borrowing money from a consortium of dentists, he learned to direct, write and produce his first short film, Xenogenesis (1978), with a friend. Learning as he went, Cameron said he felt like a doctor doing his first surgical procedure. He then served as a production assistant for Rock 'n' Roll High School (1979). While educating himself about filmmaking techniques, Cameron started a job as a miniature model maker at Roger Corman Studios. He was soon employed as an art director for the science-fiction film Battle Beyond the Stars (1980). He carried out the special effects for John Carpenter's Escape from New York (1981), served as production designer for Galaxy of Terror (1981), and consulted on the design for Android (1982).

Cameron was hired as the visual effects director for the sequel to Piranha (1978), titled Piranha II: The Spawning in 1982. The original director, Miller Drake, left the project due to creative differences with producer Ovidio Assonitis. Shot in Rome, Italy, and on Grand Cayman Island, the film gave Cameron the opportunity to become director for a major film for the first time. Cameron later said that it did not feel like his first film due to power-struggles with Assonitis. Upon release of Piranha II: The Spawning, critics were not impressed; author Tim Healey called it "a marvellously bad movie which splices clichés from every conceivable source".