CUPERTINO, Calif. -- Steve Jobs, the Apple founder and former CEO who invented and masterfully marketed ever-sleeker gadgets that transformed everyday technology, from the personal computer to the iPod and iPhone, has died. He was 56.
Apple announced his death without giving a specific cause.
"We are deeply saddened to announce that Steve Jobs passed away today," the company said in a brief statement.
"Steve's brilliance, passion and energy were the source of countless innovations that enrich and improve all of our lives. The world is immeasurably better because of Steve."
Jobs had battled cancer in 2004 and underwent a liver transplant in 2009 after taking a leave of absence for unspecified health problems.
He took another leave of absence in January -- his third since his health problems began -- before resigning as CEO six weeks ago. Jobs became Apple's chairman and handed the CEO job over to his hand-picked successor, Tim Cook.
The news Apple fans and shareholders had been dreading came the day after Apple unveiled its latest version of the iPhone, just one in a procession of devices that shaped technology and society while Jobs was at the helm.
Jobs started Apple with a high school friend in a Silicon Valley garage in 1976, was forced out a decade later and returned in 1997 to rescue the company. During his second stint, it grew into the most valuable technology company in the world with a market value of $351 billion.
Cultivating Apple's countercultural sensibility and a minimalist design ethic, Jobs rolled out one sensational product after another, even in the face of the late-2000s recession and his own failing health.
He helped change computers from a geeky hobbyist's obsession to a necessity of modern life at work and home, and in the process he upended not just personal technology but the cellphone and music industries. For transformation of American industry, he ranks among his computer-age contemporary, Microsoft Corp. co-founder Bill Gates, and other creative geniuses such as Walt Disney who left an indelible imprint on the world. Jobs died as Walt Disney Co.'s largest shareholder, a by-product of his decision to sell animation studio Pixar in 2006.
Perhaps most influentially, Jobs in 2001 launched the iPod, which offered "1,000 songs in your pocket."
In 2007 came the touch-screen iPhone, joined a year later by Apple's App Store, where developers could sell iPhone "apps" which made the phone a device not just for making calls but also for managing money, editing photos, playing games and social networking. I
n 2010, Jobs introduced the iPad, a tablet-sized, all-touch computer that took off even though analysts said no one really needed one.
Steven Paul Jobs was born Feb. 24, 1955, to Joanne Simpson, then an unmarried graduate student, and Abdulfattah Jandali, a student from Syria. Simpson gave Jobs up for adoption, though she married Jandali and a few years later had a second child with him, Mona Simpson, who became a novelist.
Steven was adopted by Clara and Paul Jobs of Los Altos, Calif., a working-class couple who nurtured his early interest in electronics. He saw his first computer terminal at NASA's Ames Research Center when he was around 11 and landed a summer job at Hewlett-Packard before he had finished high school.
Jobs enrolled in Reed College in Portland, Ore., in 1972 but dropped out after a semester.
When he returned to California in 1974, Jobs worked for video game maker Atari and attended meetings of the Homebrew Computer Club with Steve Wozniak, a high school friend.
Wozniak's homemade computer drew attention from other enthusiasts, but Jobs saw its potential far beyond the geeky hobbyists of the time. The pair started Apple in Jobs' parents' garage in 1976. Their first creation was the Apple I -- essentially, the guts of a computer without a case, keyboard or monitor.
The Apple II, which hit the market in 1977, was their first machine for the masses. It became so popular that Jobs was worth $100 million by age 25.
During a 1979 visit to the Xerox Palo Alto Research Center, Jobs again spotted mass potential in a niche invention: a computer that allowed people to access files and control programs with the click of a mouse, not typed commands. He returned to Apple and ordered the team to copy what he had seen.
It foreshadowed a propensity to take other people's concepts, improve on them and spin them into wildly successful products. Under Jobs, Apple didn't invent computers, digital music players or smartphones -- it reinvented them for people who didn't want to learn computer programming or negotiate the technical hassles of keeping their gadgets working.
"We have always been shameless about stealing great ideas," Jobs said in an interview for the 1996 PBS series "Triumph of the Nerds."
The engineers responded with two computers. The pricier one, called Lisa, launched to a cool reception in 1983. A less-expensive model, the Macintosh, named for an employee's favorite apple, exploded onto the scene in 1984.