You can assign each post to category for easier navigation. One main category is required; additional extra categories can be assigned.

You do this with the categories panel, which is located at the top of the right column on both the Post Edit Screen.

In the first column you must select the main category of the post. There can be only one main category per post.

In the second column you can select additional categories for the post. You can select several such "extra" categories for each post.

Your post will appear in all of the selected categories when browsing your blog by category. However, when the Permalink URL of your post is constructed, only the main category will be used.

Configuring this panel

This panel may have more or less available fields depending on the configuration of the current Create/Edit Options Panel.