I just found out about the Yahoo UI Reset CSS tool/file and I'm using it on my website. On my machine I have Internet Explorer 7 and Firefox 3.01 and my webpage looks the same on these two browsers. A friend is using Internet Explorer 6 and the page is completely a mess. I have two questions:
The purpose of it is that HTML(edit: the browsers have predefined properties for the elements.ty Zack) has some predefined properties for its elements like the built-in padding/margin for the paragraph element. The point of using the reset cheat sheet is to start with default values that are equal for all elements : size, margin, padding etc. I use the reset file in my project but not in its original form. You should decide which elements in the sheet to use and you can always assign other default values for the tags there.
edit: You can test your web-page by installing most of the browsers available. Here is the latest statistics representing the usage of browsers. My advice is to use Mozilla as your 1st choice testing browser and every now and then test the page on other browsers: IE6, IE7, IE8, Opera, Chrome and Safari (at least). Here is a reference to a discussion about multiple IEs on one PC. Best of luck!
For IE you can use this tool (Multiple IE) to test your website in old versions.
For the Reset CSS i redirect you to this question.
A reset CSS--of which YUI's is only one example--aim to remove browser differences in default CSS properties for HTML elements, like some browsers will have a default 8 pixel padding on the html element (it was a surprise to me to find the html element was even styled when I first found out).
Your IE6 issues are entirely separate to that. Without examples of the site itself it's impossible to say why this might be but the obvious guess is that you're relying on reasonably advanced CSS features (eg a > b selectors, :hover on non-anchors, certain positioning schemes and so on).
If you are not particular about testing in your machine, you could try http://browsershots.org. It's free and provides screenshots of your site in various browsers on Linux/Windows/Mac OS/BSD.
Just because your website looks terrible in Internet Explorer 6 does not mean you are terrible at CSS. There are several documented bugs in Internet Explorer's rendering engine in regards to CSS. Web designers and developers have been struggling with these bugs for years. Several well known websites like Digg and YouTube are no longer going to support IE6.
You have several options to test your website in multiple browsers. The easiest way is to install all the browsers you want to test against on a local machine. There are 5 major browsers, and they all require different methods to install multiple versions.
If you are using Windows XP, you can use Multiple IEs to install Internet Explorer versions 3, 4.01, 5, 5.5 and 6.
If you are using Windows Vista or Windows 7 (or Windows XP for that matter) you can download virtual machine images from Microsoft that contain a fully licensed Windows operating system with Internet Explorer. These virtual machine images expire every 90 to 120 days. They offer the following images:
These images can all be used with the free Virtual PC 2007.
You can install multiple versions of Firefox on the same operating system, but it is highly advised that you create a new profile for each version you are going to install. You can use the steps outlined on Rob Cherny's blog to set this up (the article is referring to Firefox 2, but it works for Firefox 3 and 3.5 too). Alternatively, you can use MultiFirefox.
There really isn't an easy way to run multiple versions of Google Chrome on the same machine. The fact that updates are applied automatically and silently means that you really shouldn't worry to much about designing your website for older versions of Chrome. If this is unacceptable, you will need to use virtual images as advised for Internet Explorer previously.
Safari is similar to Google Chrome in that there isn't an easy way to run multiple versions on the same machine. Michel Fortin has an article that details how to get multiple versions running on Mac OS X. You can refer to this Stack Overflow question for the lowdown on Windows. Virtual images, again, seem to be the only way to go.
You can install older versions of Opera without issue, so long as they are installed to different directories.
Google Chrome There really isn't an easy way to run multiple versions of Google Chrome on the same machine
Not true. You can have different version of Chrome in differnet user accounts.