Font-size

* CSS has many options for setting the size of font - you can apply keywords, relative values or absolute values.
* Relative Units are: em, ex, px, % or keywords.
* Absolute Units are: mm, cm, in, pt or keywords.
* 72pt = 1 inch in real life (not on your monitor).
* We don't usually use pts to control font size, unless we are using CSS for print, as there are cross browser compatability issues.
* Absolute Keywords are: xx-large, xlarge, large, medium, small, x-small, xx-small.
* Medium is set to the default text size for the browser (except in IE 5.5 or earlier).
* In Industry these are often referred to as T-SHIRT sizes.
* Relative Keywords are: larger and smaller.
* They measure relative to their parent element.
* For example, if the font-size of the body is set to 16px, any element with the font-size set to 'larger' will be larger than 16px.
* Be aware you can run in to problems if you nest elements, although many modern browsers do have thresholds in place.