Apple co-founder and CEO Steve Jobs has resigned as CEO from Apple today, after a remarkable career. He will continue with Apple as chairman of the board.

Jobs is that rare person who truly has transformed an industry and in many ways changed the daily activities of people throughout the world. He is also a controversial man, admired by many and criticized by many.

Whatever people think of him, I believe they can all agree he is fierce: fiercely loyal to his principles and to his friends and close colleagues, fiercely competitive, fierce in his ambitions, fiercely dismissive and belittling to those he does not respect or who he believes are in his way.

He is fiercely stubborn, with a bulldog-like habit of not letting go but instead continuing to persevere for as long as it took. The iPad was a decade-long project, for example). 

Famous for the Mac and iPhone, Jobs's influence has been much deeper than anyone else in a technology industry with no shortage of larger-than-life figures who also have made big differences, such as Larry Ellison, Philippe Kahn, Scott McNealy, Marc Benioff, Bill Gates, and Carly Fiorina.

Jobs changed the music industry with the iPod, the cellular phone industry with the iPhone, the movie industry with his Pixar Animation Studios films and the computing industry — with the original Mac and then again with Mac OS X and just last year with the iPad.

He has been in the middle of doing the same transformation to the publishing industry with his iBooks and media subscription services, and with the software industry with his App Store.

Many of the iconic products created under his leadership have become the models for everyone else, creating a demand for high quality, good design, and user-centric products.

That's why when you think smartphone, you think iPhone; when you think tablet, you think iPad; when you think ease of use you think Mac OS X; when you think digital music you think iPod and iTunes; and when you think of family movies you think of Toy Story.

The story of Jobs goes deeper, with some major low points along the way. His amazingly strong personality also shaped the personality of Apple.

Jobs's hate-love relationship with the Mac
Today, most people have forgotten that the Mac was not really Jobs's invention. After pioneering the Apple I and II computers with co-founder Steve Wozniak, Jobs moved on to the Lisa project at Apple.

The Mac was spearheaded by Jef Raskin, and Jobs actively worked against the Mac project to give his Lisa effort an edge. The pirate culture at Apple, detailed in spot-on detail by InfoWorld columnist Robert X. Cringely in his history Accidental Empires, was born of Jobs's decision to compete with the Mac project.

After the Lisa flopped, Jobs switched sides and took over the Mac, becoming its champion and public face. That cemented his reputation though led to his forced exit a year later.

The pirate approach also created a dysfunctional culture at Apple that grew into frightening levels by the mid-1990s, nearly destroying the company.

Product development was based on open warfare among engineering groups, resulting in inconsistent products and visions that confused customers and compromised the company's business model.

The Jobs pirate culture nearly destroys Apple
Six years after Jobs's forced departure from Apple, the Mac community was very much split between the old-time Mac cultists and the new breed of agnostic users who saw it as a great niche tool. Steve Jobs was greatly missed by the cultist crowd, and they closely followed his failed effort to reinvent networking computing with his NextStep operating system and Next Cube server and then his successful effort as cofounder of Pixar.

During the Next period, Jobs was at his most accessible, toning down his famous arrogance, though it never went away. When Pixar was acquired by Disney, Jobs disappeared from media circles.

What he was doing was learning how to work in the shark-filled waters of the entertainment industry. He learned well, as years later he became a major Disney shareholder and used his influence there to push the music industry into digital music via iTunes, changing the nature of music business. At the time the music-sharing sites like Napster were killing its sales, and all its copy-protection schemes were easily defeated.

But the iTunes deal happened after Jobs returned to Apple in 1996. In the mid-1990s, Jobs was largely absent from the Mac universe, and Apple's internal warfare intensified.

During a succession of CEOs John Sculley, Michael Spindler, and Gil Amelio tried to make Apple like every other PC maker.

The Apple engineers started to fight with management, not just each other.

Sculley was forced out, the former Pepsi exec dismissed as too much centered on image than substance.

Spindler took over as CEO, after having worked through the ranks of Apple's European arm. He made the decision to drop the Motorola 680x0 line of processors in favor of IBM's then-new PowerPC, which gave Apple a new boost of enthusiasm among both the engineers and the user base.

But the war over the PC-fication of the Mac got worse under Spindler's regime, and he soon lost control.

Apple brought in Amelio, a respected exec from National Semiconductor who tried to bring in adult supervision such as former IBM exec Ellen Hancock.

Amelio authorized Motorola and the IBM-backed Power Computing to make the first Mac clones, a move that was meant to place the Mac crown jewel in hands other than Apple's, as Apple's warfare had hit a point where the company's very viability was in question.

At the same time, the efforts to create a replacement OS for the Mac's System 8 were failing, leaving Apple without a long-term platform.

The engineers essentially closed ranks and shut Amelio out, making him and his lieutenants leaders in name only.

Amelio then did something surprisingly canny: he turned to Jobs as an adviser, then bought Jobs' NextStep OS as the basis for a new Mac OS.

Jobs's public return to Apple in early 1997 caused near-messianic waves of fervor and hope among the user community.

Jobs takes over and undoes the pirate culture he set in motion
Amelio's reward for bringing Jobs back was to lose his job in a coup that Jobs led six months later.

Once Jobs had taken over Apple, he sealed a deal with his longtime business foe, Microsoft's then-CEO Bill Gates, for a cash infusion and a commitment to keeping Office on the Mac. That deal quieted the investor fears about Apple's survival while also giving Microsoft some cover for the antitrust issues the Justice Department was then investigating.

A year or so later, Jobs released the candy-colored iMacs, which changed the idea that computers had to look like beige appliances. Derided as making computers into toys, the iMac line made computers accessible and human. Jobs had learned from Disney how important it was to have an emotional connection with your customers, and he applied that principle brilliantly to the Mac as part of his resurrection strategy.

People typically believe that Jobs does everything at Apple, but that's not the case. He has had an amazingly strong set of executives, to whom he delegates significant power and responsibility.

The two that matter the most are Jonathan Ive, the company's chief designer, and Tim Cook, the man who makes Apple work like a precision machine in its manufacturing, retail, and online spheres. Cook now succeeds Jobs as CEO at Apple.

Quiet and unassuming, it was clear that Ive was a brilliant designer. but one that Apple gave little authority to. When Jobs took over, he interviewed the existing Apple execs to see who should stay. He saw the brilliance that Ive had and gave him the freedom and burden of making elegant, innovative design and usability the fundamental quality of all future Apple products.

The result has been amazing, and Jobs protected and supported Ive in those early years. Jobs also dismantled the pirate culture he helped set in motion in the early 1980s and brought an amazing discipline to Apple.

He would bring some people to tears as he demolished what he considered to be substandard decisions and ideas. He would fire those who moved against him or his view of Apple's interests.

He would install fierce loyalty in others as he encouraged and supported the ones he believed were doing the right things. He would encourage opposing ideas, as long as the opposition was constructive. And people who work directly with him strongly admired and liked him.

Jobs kept his hand in the details and of course had the final say on the strategy. But as CEO he was no one-man band. As personally tied as Jobs was to Apple's products and success, he was no mere autocrat hurling diktats to the serfs.

Instead, he recreated the Apple culture as one of an elite squad.

In almost every case, Apple has set the bar for how things should be, so every competitor, whether it is Windows, Android, or an app store, is measured by the standards Apple, and Jobs, has set.

It takes a fierce person to do that over and over again.

Steve Jobs at Apple: A timeline