Having formally entered the computer industry in 1975 Microsoft chairman Bill Gates will semi-retire later this month. Although he will keep his title of Microsoft chairman, he will devote most of his time to working with the Bill & Melinda Gates Foundation.

There's no doubt that Gates is synonymous with Windows and the monumental impact it and other software made in delivering computing to the masses. Competitors, colleagues and industry observers point to Gates' intellect and passion that pushed an industry from infancy to maturity, but also revealed an arrogance and competitive spirit that at times had little tolerance for other winners, such as Novell, Netscape, open source and Google.

Along the way there were famous stumbles followed by famous recoveries, such as Gates' 1995 'Internet Tidal Wave' memo that declared the internet was "the most important single development" since the IBM PC at a time when Silicon Valley was already well across that bridge.

"One of the things that is interesting about Gates is the extent to which he stamped his own personality on the organisational culture of Microsoft and by extension on a great deal of the personal computing industry," says Thomas Haigh, a historian of computing at the University of Wisconsin at Milwaukee. Haigh says Gates was a combination of a techie and a businessman who really wanted to get software out the door, win market share and beat the competition.

"Putting those two things together made him distinctive among his generation of software industry leaders and explains a lot about how Microsoft developed as a company," Haigh says.

After 33 years in the business, the Microsoft co-founder is both revered and reviled.

"There are not too many people who can be Darth Vader and Luke Skywalker at the same time," says Dana Gardner, principal analyst for Interarbor Solutions, who has spent more than a decade following Microsoft and the high-tech industry. "To a lot of people he was the evil empire. He stifled innovation and creativity. He was aggressive in business. Not just aggressive, but hyper aggressive, and that did not serve Microsoft well over time."

But Gardner compliments Gates for rallying together the components to create a standard approach to desktop computing.

"Many people look at him as an example of what good business is all about and how to create good value from your own sweat and ingenuity."

Gates carved out his top spot in the industry by molding a company with $16,000 (£8,000) in sales its first year to one with more than $50bn (£25bn) in revenue today.

NEXT PAGE: Why the Gates legacy will go down in history

  1. Just what make the Microsoft CEO so revered?
  2. Why the Gates legacy will go down in history
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As Bill Gates prepares to semi-retire from the tech industry to concentrate on his charity efforts, we chart the highs and lows of his career and identify just why he'll be remembered for years to come.

The financial success, however, is only a reflection of Gates' dedication on the technology side. In 1975, Gates and Microsoft co-founder Paul Allen dove into 24-hour coding sessions in order to adapt the BASIC computer language for the Micro Instrumentation and Telemetry Systems (MITS) Altair 8800 personal computer, which was officially announced on 1 January.

The sessions produced Microsoft Basic for the Altair and by July, Gates and Allen had a licensing deal with MITS. The following year, a 20-year-old Gates gave the opening address at the first annual World Altair Computer Convention (WACC) and the legend was born.

His effort to create Basic and seize upon the Altair opportunity, which is now recognised as the starter's pistol for personal computing, was but a glimpse of the tenacity that would come to define Gates and his work ethic.

"I remember about 10 years ago being in reviews with him, and he and Eric Rudder [Gates' technical advisor at the time] being able to vet almost any technical challenge," says Keith McCall, who spent nearly five years as director and product unit manager for Microsoft Exchange Solutions and is now CTO at Azaleos. McCall recalls Gates as an "intimidating force with his intelligence and breadth. But he was always friendly in a quiet way. He wouldn't go out of his way to slap you on the back and ask how you were doing. But he always had a nod or a smile when he interacted with folks."

Gates' legacy, however, was far from all smiles.

"No doubt that Gates is a historical giant in the context of the industry," says Ed Black, president and CEO of the Computer & Communications Industry Association (CCIA), which had well-documented clashes with Microsoft during a number of the software giants anti-trust cases. "He has had a huge impact, some of it has been positive and some has not."

Black would not discuss what has not been so positive, but clearly Microsoft's status as a convicted monopolist is the darkest period in the company's history.

Gates' taped deposition as part of the US anti-trust case, in which he was openly combative, revealed to the public an arrogance not often seen outside the walls of Microsoft.

Observers have noted that Microsoft is a reflection of Gates personality, combing his arrogance with stubbornness, antagonism and outright bullying.

Historian Haigh says Gates and Microsoft also had a good deal of luck, first with the success of Microsoft Basic and then winning the contract for DOS on the IBM PC.

"It was the income stream from DOS that kept them growing exponentially in the 80s even as their other product launches were either outright failures or 'me too' products like Word for DOS," Haigh says.

NEXT PAGE: More industry opinions on Gates

  1. Just what make the Microsoft CEO so revered?
  2. Why the Gates legacy will go down in history
  3. More industry opinions on Gates

As Bill Gates prepares to semi retire from the tech industry to concentrate on his charity efforts, we chart the highs and lows of his career and identify just why he'll be remembered for years to come.

The momentum also resulted in good and bad for corporate computing, according to some analysts.

"In some ways the industry is richer because of a unified environment Gates created and in other ways it is poorer because of stifled innovation," says Dan Kusnetzky, president of the Kusnetzky Group. "People have come up with all kinds of things that are arguably better than the Windows platform and many times they cannot get heard in corporate decision making because it isn't the Windows platform."

Noted high-tech author Nelson Ruest remembers 20 years ago when Microsoft was the underdog striving to battle the big boys.

"There was an enthusiasm with everybody that was tied together with Microsoft technology," Ruest says, adding that this has unfortunately disappeared today, but he is sure of one thing. "I know for a fact that Gates basically created the job that I have. If it was not for Bill Gates, I would not have worked in IT for 20 some years."

Others agree.

"What Thomas J. Watson did with IBM was a big deal but Bill Gates went one better with a bigger, broader vision," says Kevin Hickey, president of Microsoft partner NetPro. "The economic impact of what Gates created is unfathomable."

The impact was created using his business and leadership savvy.

"Part of the success is not just Gates, but the people he has surrounded himself with," says Fred Wettling, manager of IT standards and strategies for Bechtel. "He is a tech guy, but he was shrewd to partner with [Steve] Ballmer and make him part of the company fabric." And Wettling says Gates has done an excellent job of handling his transition out of Microsoft, which he announced two years ago.

Despite his tech prowess, however, Wettling says Gates could have been better at promoting and developing industry standards at the expensive of creating divergent technologies to license to users.

"[Lack of industry standards] creates a challenge for us at Bechtel. Integration is not an easy thing," Wettling says. "In terms of standards, Microsoft is improving but it is not pretty."

So while June 27 will be Gates' last day in the office, it will be years before history will have a clear picture of his legacy.

"It is going to take some time to get a neutral perspective based on the outcome of all the things he has set in motion," Kusnetzky says. "Today, the sides are too polarised."

But many believe that technology will only be secondary in future discussions on the legacy of Gates.

"Long after people have forgotten about the Blue Screen of Death and the browser wars, there might be a cure for malaria or the ability to pay for AIDS medications in impoverished countries," Gardner says.

  1. Just what make the Microsoft CEO so revered?
  2. Why the Gates legacy will go down in history
  3. More industry opinions on Gates