To table or not to table?

• "The HTML table model allows authors to arrange data"
• Does it make sense to put it in an Excel document?
• Am I using tables for formatting & not formatting tables?
• Am I formatting elements to have tabular behavior?

PX vs. EM

• PX = One atomic unit of measure.
• EM = Width of the character 'M'.
• PX is fixed, EM is fluid.
• EM is percentage in CSS, 1.5 = 150%

Resources

• CSS 2.1 Spec
• CSS 3.0 Working Draft
• CSS Validator
• HTML 4.01 Spec
• HTML5 Editor's Draft
• HTML Validator
• W3C