Hi, about 4-5 years ago I made several websites for myself and friends, I was thinking of getting back into it but I wanted to ask for an update on the current state of certain things. I wrote using HTML 4.01, and leaned towards a minimalist approach to coding, including omitting unnecessary tags (head, body, etc…). At this moment, HTML 5 is still under development, but I see that many websites use it, so how does that work as far as browser compatibility? Do they support (features of) HTML 5? And do they display HTML/CSS more consistently (are “if IE” comment tags still neccessary for most pages)? Depending on target audience obviously, but what browsers are we checking now while coding? Firefox, IE (versions?), Opera, Chrome, Safari? I also came across something called HTML 5 boilerplate, so I wanted to see some thoughts on that as well before I go into studying it and HTML 5 in more detail.
Hi snowlep. Welcome to the forums. 
HTML 5 is still under development, but I see that many websites use it, so how does that work as far as browser compatibility? Do they support (features of) HTML 5?
The most advanced browsers are starting to support little bits of it, but on the whole, it is mostly not supported yet. HTML5 is changing daily anyway, so it’s a bit of a risk to predict what it will finally look like.
And do they display HTML/CSS more consistently
No. There’s no difference.
(are “if IE” comment tags still neccessary for most pages)?
Yes, if you want to iron out older browser bugs. The latest IE (10) doesn’t use them (actually, maybe it’s 9), though.
Depending on target audience obviously, but what browsers are we checking now while coding?
Ideally, all of them.
IE6 and 7 are basically dead, so I don’t test them any more. But IE8 and 9 defiantly. The other browsers tend to auto update, so it’s fairly safe to test the latest versions. Safari is no longer being made for PC, which is a bit of a pain for Windows users, but it doesn’t have a high userbase anyway.
Don’t forget the mobile browsers, though. That’s “a whole nuther” kettle of fish … It’s the rather scary, brave new world of web development.
I also came across something called HTML 5 boilerplate, so I wanted to see some thoughts on that as well before I go into studying it and HTML 5 in more detail.
Yes, there are lots of tools out there which basically act as a life support systems for websites using tomorrow’s technologies today. People use JavaScript and what not to help browsers understand HTML5. IMHO they are a bloated waste of time, but to each his/her own.
Thanks for the welcome and thoughts.
Don’t forget the mobile browsers, though. That’s “a whole nuther” kettle of fish
I didn’t, I know I’m going to have to do some studying on my own to include them, especially since they’re ubiquitous now. Tablets, too… wow. However, I’m getting a lot of interesting hits searching this so their seems to be enough interesting information on this that’s easy to get by myself, and to make the smartest choices.
I usually did some kind of “elastic/fluid” hybrid with a min and max width for columns, also making use of the em unit since it changed with text size, but I think most browsers ditched the text size and went for zoom instead. And now with these huge variances in resolution… yup, I definitely have some reading to do on CSS, but I’m happy http://www.quirksmode.org/css/contents.html is still being updated.
Yes, there are lots of tools out there which basically act as a life support systems for websites using tomorrow’s technologies today. People use JavaScript and what not to help browsers understand HTML5.
That’s something that didn’t occur to me, would probably be pointless for my purposes. Reminds me of serving XHTML as html.
Indeed, yes—a situation that still persists. 
The good thing is that standard CSS2.1 and HTML4 are really well supported in browsers now, so if your code is clean, well formed and not too ambitious, browsers don’t present much of a problem these days.
The latest IE (10) doesn’t use them (actually, maybe it’s 9), though.
Conditional comments were deprecated in IE10. Also the CSS filters and some other stuff.
But IE8 and 9 defiantly.
Defiance is awesome.