Dividing the desired line height (18px) by the element font size (12px) gives us the em value for line height. In this example, the line height is 1 and a half times the font size: 1.5em.
Add line height and margin properties to the CSS:
p{
font-size: 0.750em;
line-height: 1.5em;
margin: 1.5em;
}
Now the browser will say to itself, “Oh, line height and margin is set to 1.5em, so that should be 1.5 times the font size. What’s the font size, again? 12px? OK, cool, make line height and margin 1.5 times that, so 18px.”
Jochen Burkhard on 25 Jun 10Summary: A key part of any Asynchronous JavaScript and XML (Ajax)-based web application is the communication layer between the client and the server. To implement this layer, you need to understand the various communication mechanisms that browsers provide, as well as each mechanism's pros and cons. In this article, learn to make the correct match between the specific communication needs of an application and the appropriate mechanism. Detailed examples show you how to create a communication layer that can meet these different client-server communication needs.
