When you set up your blog you can define the categories you want to use. These categories can be anything you, as the owner of the blog, want them to be. Naturally, you would want the categories to be related to the broad themes of your blog. The categories would then serve as a natural way to organize the material you post. The categories are typically listed as links in the sidebar of your blog. When a user clicks on one of your category links, only the posts you have assigned to that category appear in the main area of your blog.

If you are using your blog as a central hub for your classroom, you might decide to use categories like these:

• Assessments
• Extend Your Learning
• General Information
• Homework
• Projects
• Podcasts
• Student Posts
• Today In Class

Each post you publish is then associated with one or more of your categories. So if your post contained general information, such as your classroom policies (including your guidelines for turning in homework), you could assign the post to the two categories: "General Information" and "Homework." You would want the categories you create and associate with each post to appear logical to the user.

Some blogging systems even allow you to have two types of categories: Top Level Categories and Subcategories. These usually appear in an outline format in the sidebar. The subcategories are indented under the top level categories. You can find an example at this blog called Podcast Central.

A word of caution: Don't create too many categories as you might make finding information on your blog too complicated for your readers. And, conversely, don't have too few categories.

And one final thing: Blogger refers to categories in two ways. Sometimes they call them labels and sometimes they call them categories.