As mentioned in previous posts, I spend some time on web design-related forums so a lot of what I've written on this site has been in response to questions I see asked quite often. This post is not so much about a question, but a reaction.
Quite often people new to creating CSS-only layouts will say:
My site looks fine in IE... to which there will often be the reply:
Don't use IE as your primary testing browser, you should use a browser with more up-to-date CSS support, like Firefox.
And just sometimes this will provoke a strong reaction from someone along the lines of:
"Internet Explorer is used by more than 90% of all web users! You can't just ignore it!!"
No-one's suggesting that IE be ignored
The problem appears to be that the person who has reacted this way has got as far as Don't use IE and stopped reading. Or maybe they've kept reading but been unable to take in the rest of the words due to the shock they've been induced into by such an outrageous statement until they get to the end of the sentence and see the word, 'Firefox', at which point they think it's another IE v Firefox issue and jump in to defend IE.
The reality is that no-one's suggesting that developers not test in IE. Nine times out of ten the person suggesting using a browser other than IE to test in has a better understanding of CSS cross browser issues (which means making layouts look right in all browsers) than the person getting upset. The suggestion to not use IE as a primary testing browser has nothing to do with personal browser preference or about Firefox trying to win the browser war (if one really exists) with IE; it's all about simple common sense.
I wonder if these people defending the use of IE would seriously consider developing their sites first in IE5. Of course they wouldn't because IE5 is an old browser. Well, so is IE6, having not received a non-security update in more than five years! And as such, IE6 has less than complete support for CSS2 with numerous, well-documented bugs.
Using a 'newer' browser
Maybe these sort of misunderstandings could be avoided if people suggested using a browser newer than IE6 as their primary testing browser. Even IE7 would be a much better choice for a primary testing browser than IE6 as it has better CSS2 support and has fixed a whole raft of the bugs that plague IE6.
Because the reality is, if you develop your site in IE6 and get it how you want it, when you come to look at it in other browsers, you'll more than likely encounter a whole series of problems that require some serious reworking to overcome. If you start off with a non-IE6 browser first, the chances of your site looking right in nearly all other modern browsers (which includes the Gecko-based family Firefox, Mozilla, Seamonkey, Netscape and Camino Opera, Safari and Konqueror) is very high with the only additional work required to add a few special rules to overcome bugs in IE6 and the broken box model in IE5.
Using a browser with up-to-date CSS support means you will spend less time developing a site and if you're a professional developer, saved time equates to saved money. If you're a hobbyist, you might find it a useful learning exercise to use what I consider the 'backwards' approach and start your design in IE6 and then try to get it right in the others. I doubt many would want to continue with that approach for too long though. I mean, who wants to do twice the work every time they create a layout?
Browser testing suite
I've been referring to 'primary' testing browser throughout this post and that's because a lot of developers will work mainly in one browser when developing their site and then check it in others at the end to make sure it looks OK.
While this is an acceptable practice, an even safer one would be to actually have a three-pronged testing suite consisting of Firefox, Opera and IE6 and testing periodically in all three as you go along. With the arrival of an official public release of IE7 imminent, this may need to be expanded.
You will find that Firefox and Opera will be mostly the same but checking in IE as you go will enable you to catch the potential problems (quite often caused by hasLayout) and find ways to fix them that may be able to be incorporated into your main stylesheet without having to add too many hacks or rules to an IE-only stylesheet.
Even though I'd recommend using those three (or four) browsers when developing a site, I do have a personal favourite for the job, and I explain which and why in Developing your site using Firefox.