Hi everyone,
With the recent developments in web typography: web fonts, latest browser upgrades, higher screen resolutions, mobile devices, iPhone, iPad, responsive Web Design, etc, what's the best practice when it comes to setting type on the web, is it better (in terms of usability, accessibility, readability) to set the font size in pixels or ems? What about the margins, padding and line-height?
All methods are valid.
The argument against pixels in the past was that, as usual, Microsoft screwed things up and IE couldn't resize type set in PX. If that's still a concern, use anything but pixels. Most modern browsers now scale the entire page and can deal with pixel units just fine.
In terms of accessibility and usability, make sure you aren't using an insanely small default font size setting and aren't going nuts with the contrast (too much or too little). As for readability, stick with your design skills. Most of the same rules apply online as they do on paper.
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