In the late 1970s, Jobs, with Apple co-founder Steve Wozniak, Mike Markkula, and others, designed, developed, and marketed one of the first commercially successful lines of personal computers, the Apple II series. In the early 1980s, Jobs was among the first to see the commercial potential of the mouse-driven graphical user interface which led to the creation of the Macintosh. After losing a power struggle with the board of directors in 1985, Jobs resigned from Apple and founded NeXT, a computer platform development company specializing in the higher education and business markets. Apple's subsequent 1996 buyout of NeXT brought Jobs back to the company he co-founded, and he has served as its CEO since 1997.

In 1986, he acquired the computer graphics division of Lucasfilm Ltd which was spun off as Pixar Animation Studios. He remained CEO and majority shareholder until its acquisition by the Walt Disney company in 2006. Jobs is currently a member of Disney's Board of Directors.

Jobs' history in business has contributed much to the symbolic image of the idiosyncratic, individualistic Silicon Valley entrepreneur, emphasizing the importance of design and understanding the crucial role aesthetics play in public appeal. His work driving forward the development of products that are both functional and elegant has earned him a devoted following.

Jobs is listed as either primary inventor or co-inventor in over 230 both awarded patents and patent applications related to a range from actual computer and portable devices to user interfaces (including touch-based), speakers, keyboards, power adapters, staircases, clasps, sleeves, lanyards and packages.

Jobs was born in San Francisco and was adopted by Paul and Clara Jobs (née Hagopian) of Mountain View, California, who named him Steven Paul. Paul and Clara later adopted a daughter, who they named Patti. Jobs' biological parents – Abdulfattah Jandali, a Syrian Muslim graduate student who later became a political science professor, and Joanne Simpson, an American graduate student who went on to become a speech therapist – later married, giving birth to and raising Jobs' biological sister, the novelist Mona Simpson.

Jobs attended Cupertino Junior High School and Homestead High School in Cupertino, California, and frequented after-school lectures at the Hewlett-Packard Company in Palo Alto, California. He was soon hired there and worked with Steve Wozniak as a summer employee. In 1972, Jobs graduated from high school and enrolled in Reed College in Portland, Oregon. Although he dropped out after only one semester, he continued auditing classes at Reed, such as one in calligraphy. Jobs later stated, "If I had never dropped in on that single course in college, the Mac would have never had multiple typefaces or proportionally spaced fonts."

In the autumn of 1974, Jobs returned to California and began attending meetings of the Homebrew Computer Club with Wozniak. He took a job as a technician at Atari, a manufacturer of popular video games, with the primary intent of saving money for a spiritual retreat to India.

Jobs then traveled to India with a Reed College friend (and, later, the first Apple employee), Daniel Kottke, in search of spiritual enlightenment. He came back a Buddhist with his head shaved and wearing traditional Indian clothing. During this time, Jobs experimented with psychedelics, calling his LSD experiences "one of the two or three most important things [he had] done in [his] life". He has stated that people around him who did not share his countercultural roots could not fully relate to his thinking.

Jobs returned to his previous job at Atari and was given the task of creating a circuit board for the game Breakout. According to Atari founder Nolan Bushnell, Atari had offered US$100 for each chip that was reduced in the machine. Jobs had little interest or knowledge in circuit board design and made a deal with Wozniak to split the bonus evenly between them if Wozniak could minimize the number of chips. Much to the amazement of Atari, Wozniak reduced the number of chips by 50, a design so tight that it was impossible to reproduce on an assembly line. At the time, Jobs told Wozniak that Atari had only given them $700 (instead of the actual $5000) and that Wozniak's share was thus $350.

In 1976, Steve Jobs, Steve Wozniak and Ronald Wayne, with later funding from a then-semi-retired Intel product-marketing manager and engineer A.C. "Mike" Markkula Jr., founded Apple. Prior to co-founding Apple, Wozniak was an electronics hacker. Jobs and Wozniak had been friends for several years, having met in 1971, when their mutual friend, Bill Fernandez, introduced 21-year-old Wozniak to 16-year-old Jobs. Steve Jobs managed to interest Wozniak in assembling a computer and selling it. As Apple continued to expand, the company began looking for an experienced executive to help manage its expansion.