James was born on December 30, 1984, in Akron, Ohio, to Gloria Marie James, who was 16 at the time of his birth. His father, Anthony McClelland, has an extensive criminal record and was not involved in his life. When James was growing up, life was often a struggle for the family, as they moved from apartment to apartment in the seedier neighborhoods of Akron while Gloria struggled to find steady work. Realizing that her son would be better off in a more stable family environment, Gloria allowed him to move in with the family of Frank Walker, a local youth football coach who introduced James to basketball when he was nine years old.

James began playing organized basketball in the fifth grade. He later played Amateur Athletic Union (AAU) basketball for the Northeast Ohio Shooting Stars. The team enjoyed success on a local and national level, led by James and his friends Sian Cotton, Dru Joyce III, and Willie McGee. The group dubbed themselves the “Fab Four” and promised each other that they would attend high school together. In a move that stirred local controversy, they chose to attend St. Vincent–St. Mary High School, a private Catholic school with predominantly white students.

Standing 6 feet 9 inches (2.06 m) tall and weighing 250 pounds (113 kg), James has played the majority of his career at the small forward and power forward positions but has also been deployed at the other positions when necessary. His playing style, which is athletic and versatile, has drawn comparisons to Hall of Famers Oscar Robertson, Magic Johnson, and Michael Jordan. Through the 2020–21 season, James’s career averages are 27.0 points, 7.4 rebounds, 7.4 assists, 1.6 steals, and 0.7 blocks per game. Since 2011, he has been ranked the best player in the NBA by ESPN and Sports

As an 18-year-old rookie, James led the Cavaliers in scoring. He holds numerous “youngest to” distinctions, including being the youngest player to score 30,000 career points. During his first stint in Cleveland, he was primarily used as an on-ball point forward, and although his shooting tendencies were perimeter-oriented, he established himself as one of the best slashers and finishers in basketball. His combination of speed, quickness, and size often created matchup problems for opposing teams because he was capable of blowing by larger defenders and overpowering smaller ones. These qualities became more apparent in transition, where he developed a reputation for grabbing defensive rebounds and then beating the defense downcourt for highlight reel baskets. Around this time, James was frequently criticized for not having a reliable jump shot or post game. Teams would try to exploit these weaknesses by giving him space in the half court and forcing him to settle for three-pointers and long two-pointers, a strategy famously used by Spurs coach Gregg Popovich in the 2007 Finals, where James converted on only 36 percent of his field goals in four games.

In Miami, Heat coach Erik Spoelstra changed James’s role to a more unconventional one. James spent more time in the post and improved his shot selection and accuracy on jump shots. He also learned how to work as an off-ball cutter in the Heat’s “pass-happy” offense. Behind these improvements, James’s overall scoring efficiency rose to historically great levels. During this time, ESPN’s Tom Haberstroh called James’s free-throw shooting his biggest weakness, describing it as “average”. Upon returning to the Cavaliers, James began to experience subtle age-related declines in productivity, posting his lowest scoring averages since his rookie season in 2015 and 2016. His shooting also temporarily regressed, and he briefly ranked as the NBA’s worst high-volume shooter from outside the paint. Despite these changes, he remained an elite offensive player who beat defenses with body control, strength, and varying attacking speeds.

For most of his career, James has controlled the offense as the primary ball handler on his team. His playmaking ability is generally considered one of his premier skills, and some analysts rank him among the greatest passers in NBA history. By exploiting his size, vision, and the attention he garners from opposing defenses, James creates easy points for his teammates with accurate assists. He executes unconventional passes, including after leaving his feet and through defensive traffic. His uncanny tendency to find the open man has helped force NBA teams to incorporate some elements of zone into their schemes to better cover the weak side of the court and prevent James from passing to open shooters. Early in James’s career, he was criticized for overpassing in pressure situations; specifically, for passing instead of shooting in the waning seconds of close games. However, as his career progressed, James’s clutch performance was viewed more favorably.

At the beginning of James’s NBA career, he was considered a poor defensive player, but he improved steadily through the years. In 2009, he became proficient at the chase-down block, which involves coming in from behind the opposition in transition to block the shot. In Miami, he developed into a more versatile defensive player, and the Heat relied on him to guard all five positions. Along with Shane Battier and Dwyane Wade, Miami used James in an ultra-aggressive defensive scheme, with James cheating off the ball to help out inside or get into rebounding position. Beginning in 2014, some analysts reported a regression in his defensive impact, stemming from a lack of effort and expected age-related declines. During his second stint in Cleveland, his defense progressively declined. After missed drives on offense, he often dawdled back on defense while complaining to the referees; he provided less help off the ball, and was less aggressive in switching. James himself admitted to taking plays off at times, referring to this approach as “chill mode”. He eventually developed a reputation for raising his defensive level in the playoffs, which some analysts referred to as “Playoff LeBron”.