px, ems, % - which to use?

Hi guys. Rookie question.

What are the standards of size/measurement one should be using when building a site? Are there any? For example, both ems and % can be used for padding. What do you guys use for text, padding, margins, etc.?

Id like to use whatever is interchangable in firefox/IE, if it even exists.

(P.S. - Im still reading/learning about CSS/Html, and haven't started any new work on my site, so this question could be completely ridiculous. I used some crappy wysiwyg editor to build a website about a year ago, where you don't have to know css/html, or anything else. You just type and click. I wanted to do it right, so thats where Im at right now. )

 

Both are supported. IE may give problems from time to time due to the improper/buggy models it follows, but that's a different issue.

Study the css specs. The basis for computing the end values are different for the two metrics and can cause grief if you don't understand what's going on.

The differences tend to be philosophical. For example, do you want sizing based on the window size, with the page containers resizing with the user resizing his browser, or do you prefer to base container size on the font size, with sizes remaining proportional to the user's preference in font size?

There's nothing wrong with fixed px sizes, either. It all comes down to your philosophical approach and the page itself; what's right in that case.

cheers,

gary

 

So, basically, it depends on the situation?

 

That and your attitude.

cheers,

gary

 

Hi,

From the sound of your first post you have absolutely the right attitude

Basically, note that em (font height) and ex (font width) measurements depend on the text size and so will change if the page is zoomed.

If you're clear on that point then the rest is purely down to your design principle as Gary said.

- P

 

Personally I use font-size: medium; than percentage width it from there. It's better to use relative units for font-size especially as IE6 can't increase the font-size if it's in px units.
Ems for lines, paragraph and sometimes if I want some height on a particular layer that contains text.
Px for certain fixed width and heights
and percentage width on fluid layouts.

I rarily touch, ex, pt or other units of measurement

 

I use pt for text which corresponds to font sizes in most applications and also scales in IE.

 

Points, or pt, are a bad unit to use for the internet because it's an absolute font-size rather than a relative one.

Have a read here on points: http://css-discuss.incutio.com/?page=UsingPoints

 

That's why modern browsers allow you to change the text size

- P

 

If you want to stick with pt sizes, that's fine. It still doesn't make it a good and accessible unit to use.

 

For better compatibility, use em instead of px as it goes well both with firefox and IE