Some people like to sort their posts in archives listed by category. This is a matter of preference, because I find it just as easy to sort subject matter by Labels, particularly because I make most of my subjects one or two words.

But say, if your giving writing lessons, and your on the subject of Dialogue. You could lists your posts under that Archive as such:

Tightening the Tension and Suspense
Using Dialogue To Reveal Story Setting
Using Dialogue To Set The Mood
Dialogue That Propels The Story Forward

See, all of those titles wouldn't work very well as one word Labels.

So this gives you a good example of the usage of Category Archives.

Okay...how do you do this?

Start on your Dashboard>>> Layout>>> Settings>>> Archives. When you 'Enable Post Pages' Click Yes, then Save. This will give each post its own url, in addition to appearing on your blog's front page.

Now go to your Template. You see that tab to the right of the Settings tab.

Click Template...the Page Elements automatically opens up. Click Add Page Element (the dotted box at the top of your sidebar list). From the screen that pops open Choose Link List.

A Configure Link List box pops open.
Add the URL of each post and its title, then click Add Link. Do this for all your posts or for those posts in one Category. Give a title to the Link List same as your
category label...then Save.