Cascading style sheets is just that, a styling sheet. HTML and CSS work together to style your website: font, color, background, position of divs, widths and heights, etc.
There are two ways to make your CSS work with your HTML: One is to write your CSS in between the head tags of your HTML file like this:
How CSS works
This text will appear small, green, and in arial.
Another way is to link your HTML file to a separate CSS file.
How CSS works
body content
This website should help you understand CSS a little better and maybe even teach you how to use it.
CSS is a language you can use instead of using html itself for describing the format in which a web page is displayed. html (or xhtml) becomes the "bones" and CSS becomes the "skin".
For example, instead of
< b>This is bold print< /p> you'd write it with
This is bold print.
(I've added extra spaces in the html for Yahoo!)
...Better yet, you'd put it as,
This is bold print< /p>
...then, somewhere in a CSS file you'd have
p.meeting { font-weight: bold; }
...and later, if you decide you want meetings displayed in small print instead of bold print, you could just change all meetings in all html files by changing that one CSS file to say,
p.meeting { font-size: smaller; }
...saves time, que no?