Single post in Styleclass and You: An Introduction

I was wondering how you make tabs appear with style formatting. I've been using only CSS and I've found out that the only way to make tabs from scratch with with style instead. Perhaps might anyone be willing to explain how to make a tab that only shows information when clicked on/have a curser hover over it? Or even buttons that make differnet text visable when clicked? (the hover code I believe) I was looking in this guide to try and find out about this sort of thing but I'm completely lost. I've tried looking at other people's tab codes to see if I could make any sense of it but obviously the tabs they have aren't the only styles that they include, and it's mixed with lots of other code which causes me to end up even more confused. Any help would be greatly appriciated ^^;