Let’s put some of your test posts into categories so you can see how this works.
WordPress Admin Manage Posts

Click on the Posts button > click on Categories link.  To the right are three links that say: View – Edit – Delete. Click on Edit to edit one of the posts. On the right side of the Edit Post screen you will now see your Categories. Choose one of them by clicking in the box next to it. Then scroll down the page and click SAVE. Repeat this for your other test posts, putting each one in a different category.

Now view your page by clicking View Site at the top of the Admin panel. Do you see the categories listed in the sidebar now? Great. If you are missing a category, that usually means that there are no posts in it. This is the default function of WordPress, so not to worry. When you add a post to the “missing” category, it will appear on your web pages. Click on one of the categories and you will be taken to a page for just that category. You should see the posts that went into that category. This is a generated Category page.

Now, click on the Archives for the month showing. Now you are visiting a generated page of your posts listed in chronological order for this month – well, specifically for today only. Two methods of finding the same information.