"I didn’t see it then, but it turned out that getting fired from Apple was the best thing that could have ever happened to me." So said Steve Jobs when addressing Stanford University in 2005. "The heaviness of being successful was replaced by the lightness of being a beginner again. It freed me to enter one of the most creative periods of my life."

Steve Jobs resigns from Apple

Jobs, who has resigned as Apple’s CEO to be replaced by COO Tim Cook, was ousted back in 1985 after falling out with the board over the future direction of the company.

It was his largely his company of course, started ten or so years earlier with Steve Wozniak and launched with the Apple I. The company really took off with the Apple II, released in 1977. It was the first successful mass-produced microcomputer product.

But after a number of disappointing product releases – the Lisa primarily and to a lesser extent the Macintosh, which was backed by a $1.5m Super Bowl commercial directed by Ridley Scott – Jobs was forced out of the company following a power struggle with CEO John Sculley.

The move worked out well for Jobs, as he founded NeXT and bought Pixar, but Apple’s struggles continued. The company nearly went bankrupt as it struggled to compete with Windows PCs dominating the market, Sculley left and the company bought NeXT, which led to Jobs’s return to the company in 1996.

Jobs was back at the company he loved, doing what he does best – designing products that people want to buy. "Your work is going to fill a large part of your life, and the only way to be truly satisfied is to do what you believe is great work. And the only way to do great work is to love what you do," he said during that Stanford lecture.

And that’s what he did. He turned the company around – hiring Tim Cook and persuading iPod designer Jonathan Ive to stay were two decisions Apple is still benefiting from.

Stories suggest the Apple leadership team, which is still very similar to the one he put together when he regained control, says no to a huge number of projects every year in order to focus on a smaller number of projects.

Apple’s recovery started with the iMac, the colourful all-in-one PC that sold nearly one million units in six months. It helped the company regain some of the popularity it had lost during its struggles of the late 80s and early 90s.

But it was the release of the iPod that changed not only Apple, but the music industry itself. The portable MP3 player has shifted around 300 million units since its introduction in 2001. This was followed shortly after by the introduction of iTunes, Apple’s online music store that offered song downloads for $.99. iTunes revolutionised the way people bought music and its combination with the iPod changed the way we listen to it.

Jobs’s idea that people should be able to carry around their music collection in their pocket – of course in a sleek handheld design – was expanded to other elements of our everyday lives. Why not the internet as well? And emails? And a camera? Step forward the iPhone.

It can be argued that there was nothing particularly revolutionary about the iPhone when it first launched, everything you could do on it you could do on other smartphones already available (and probably at a cheaper price).

But it was the combination of everything on one device coupled with its excellent user interface that saw the iPhone quickly established as the must-have smartphone. Software that was designed specifically for the hardware meant the two would work in perfect harmony, and work just as Jobs had intended.

Jobs’s refusal to separate the device from the ecosystem can be contrasted with Android’s approach, which has resulted in a number of different versions running across a number of different devices, with updates pushed out at the behest of the carriers and hardware makers rather than Google.

Around this time Jobs also oversaw the launch of the App Store, allowing iPhone and iPod Touch users to download applications to their devices, from games to social network apps to news and sports apps. Since its launch in 2008 the store has seen over 15 million downloads of half a million apps.

What was so impressive about the iPod and iPhone was that Apple introduced them into markets that, while relatively small, were certainly well established and, basically, improved on what was already available.

Apple’s next move was slightly different. The market for tablet computers had been dominated by rugged devices mainly used in warehouses, airports and so on. They were not big in the consumer world. Indeed Jobs himself had reportedly once dismissed ideas of an Apple tablet by asking: "What are they good for, apart from surfing the web on the toilet?"

But Apple clearly saw a space. "The iPad creates and defines an entirely new category of devices that will connect users with their apps and content in a much more intimate, intuitive and fun way than ever before," Jobs said at its launch. That too sold in huge numbers – 30 million in little over a year.

It also forced Apple’s rivals into a desperate race to grab a slice of the action. They have had mixed results, with Google’s Android ecosystem gaining some ground but HP’s TouchPad discontinued after just over a month on sale, BlackBerry’s PlayBook beset by mediocre reviews and Samsung’s Galaxy Tab caught up in an ugly patent battle with Apple.

Earlier this year Apple briefly overtook Exxon Mobil to become the most valuable company on the planet and quarter after quarter Apple is reporting huge turnover and profit: a remarkable turnaround for the company Jobs built. Twice.