Why is it that text is coded like 1em and 1.7em, etc. To be honest, I am not very familiar with this type of coding. Why is this style chosen over say px amounts?
I have just found this style to be very hard to understand over the normal pixels coding.
em is very common way of specifying css…
if you google about it you will see the two ‘best’ ways of specifying fonts sizes are em or %… then everything is in relation… of course, like so many other things on the web, there will be varying thoughts! 
It is the best available in the css/browser world for accurate scaling I believe and is a printer’s measurement. (Printer as in text on paper – not HP Inkjets!)