Cascading Style Sheets
Cascading Style Sheets have been around for a while now. Not everyone uses them as at first glance it can be a bit intimidating when you can fairly comfortably accomplish what you need using straight HTML. The advent of Cascading Style Sheets (CSS) is what has made Content Management Systems, blogs, and many commercial sites (from Amazon to Cafepress) is easy to use as they are. CSS is used to define a look and feel, making it easy to reproduce that same look on all of your site's pages.
I have to admit that I am still something of a novice at it. Having decided to break out of the mold of using pure HTML, I am making headway at learning to use it. I have in recent years delved only lightly in it; just enough to fine-tune the look of sites using a variety of CMS applications (Movabletype, Word Press, Mediawiki). For a home-rolled HTML site, I was still relying heavily on pure HTML with little, if any CSS definitions.
Way back in the dark ages of the WWW, when I set up my first website, the thing to do was use pure HTML, and use tables to lay out a multi-column page. This is not the way to correctly implement a multi-column page when you can do it in CSS. The E-Corps site is now using CSS to define a two-column page layout.
As mentioned elsewhere, CSS, along with javascript (for Internet Explorer compatibility), is what is being used to implement the site navigation located in the sidebar on the left of the page.
If you are serious about running a website, and want it to look its absolute best, then consider taking the time to learn CSS. Once you do, you'll begin to not only appreciate it, but be able to better harness the power of the web.
