It terms of how (from memory + fact checks on Wikipedia):
Microsoft and Netscape battled over browsers throughout the late 90s with Netscape starting in the position of the dominant/only browser and IE was seen as a joke, that quickly, by the time IE5 (1999) was released Netscape seemed completely in technical debt with it's product when they couldn't support even the most basic CSS support in Netscape 4.x. IE5 was also the release that added support for what is now called AJAX.
IE6 was released August 2001, at which point it had most of the market, IE also existed for the Mac and most people I knew at the time thought of Mozilla/Netscape as completely irrelevant as a development target. Opera has basically always been irrelevant in my view. This started an era of IE-only sites which further damaged the competition.
Microsoft disbanded it's IE development team and it wasn't until a few years later that people realized that this happened (It wasn't announced till 2003) - people seemed to assume Microsoft was working on new version of IE, which was natural since it was pretty much the only browser in town.
WHATWG was formed in 2004 so everyone else (except Microsoft) could work on web standard because this had basically stopped at that point.
Firefox wasn't released till November 2004, which was the first time it looked like there would be a credible threat to IE (though it had been pretty good for a year before with Mozilla, but still unknown to most).
IE7 was released in October 2006, by which point web developers who had been trying to more and more with the web were thoroughly frustrated with IE and it's rendering bugs. IE7 was a big disappointment because it whilst it fixed some long standing problems like it's box model, it was still a long way off the standards that had been produced since IE6 and it didn't pass that Acid2 test.
In terms of why:
I've wondered why for a long time now. Mostly, I think IE6 was already too good at being web application platform and Microsoft was worried (as they had been with Java) that this would make Windows irrelevant. Given that IE was effectively free the probably assumed there would be no viable competition due to the lack of business model. Microsoft stopping work on IE they could allow websites to work, but continue to make web apps that were too clunky to use so people would write native Win32 apps.
Reasons for "why" not often discussed: 1) Vista consumed the top systems devs at Microsoft for seven years 2) the IE team wasn't "disbanded" so much as loyal to management at Microsoft that was discarded (Brad Silverberg, David Cole) 3) enterprise customers were plenty happy with IE6 4) the dotcom bust quieted the indie developer ecosystem 5) Microsoft honestly thought they could get NT kernels + .NET on small devices and leverage massive developer support and existing tooling in the late 90s.
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It terms of how (from memory + fact checks on Wikipedia): Microsoft and Netscape battled over browsers throughout the late 90s with Netscape starting in the position of the dominant/only browser and IE was seen as a joke, that quickly, by the time IE5 (1999) was released Netscape seemed completely in technical debt with it's product when they couldn't support even the most basic CSS support in Netscape 4.x. IE5 was also the release that added support for what is now called AJAX.
IE6 was released August 2001, at which point it had most of the market, IE also existed for the Mac and most people I knew at the time thought of Mozilla/Netscape as completely irrelevant as a development target. Opera has basically always been irrelevant in my view. This started an era of IE-only sites which further damaged the competition.
Microsoft disbanded it's IE development team and it wasn't until a few years later that people realized that this happened (It wasn't announced till 2003) - people seemed to assume Microsoft was working on new version of IE, which was natural since it was pretty much the only browser in town.
WHATWG was formed in 2004 so everyone else (except Microsoft) could work on web standard because this had basically stopped at that point.
Firefox wasn't released till November 2004, which was the first time it looked like there would be a credible threat to IE (though it had been pretty good for a year before with Mozilla, but still unknown to most).
Acid2 test was created 2005 which further highlighted the problems with IE6's rendering: http://en.wikipedia.org/wiki/Acid2.
IE7 was released in October 2006, by which point web developers who had been trying to more and more with the web were thoroughly frustrated with IE and it's rendering bugs. IE7 was a big disappointment because it whilst it fixed some long standing problems like it's box model, it was still a long way off the standards that had been produced since IE6 and it didn't pass that Acid2 test.
In terms of why: I've wondered why for a long time now. Mostly, I think IE6 was already too good at being web application platform and Microsoft was worried (as they had been with Java) that this would make Windows irrelevant. Given that IE was effectively free the probably assumed there would be no viable competition due to the lack of business model. Microsoft stopping work on IE they could allow websites to work, but continue to make web apps that were too clunky to use so people would write native Win32 apps.
Reasons for "why" not often discussed: 1) Vista consumed the top systems devs at Microsoft for seven years 2) the IE team wasn't "disbanded" so much as loyal to management at Microsoft that was discarded (Brad Silverberg, David Cole) 3) enterprise customers were plenty happy with IE6 4) the dotcom bust quieted the indie developer ecosystem 5) Microsoft honestly thought they could get NT kernels + .NET on small devices and leverage massive developer support and existing tooling in the late 90s.