What is a Taxonomy?
A WordPress taxonomy is a categorization tool used to group similar posts and other content. Properly using taxonomies on your website can help improve search engine rankings.
More About Taxonomies
A category is a broad grouping of posts. For example, if you run a movie blog, your categories can be Suspense, Thriller, Comedy, Horror, Romance, Animated, etc. A post is assigned Uncategorized if you do not identify a category for it.
Categories are also hierarchical. Therefore, you can create subcategories to be more specific.
To add a new category in WordPress, navigate to Posts > Categories. To add them to a post, click on the gear icon in the top-right of the edit post screen. Then, select the Categories panel to choose the categories or add new ones.
On the other hand, tags create a topic-specific taxonomy. For instance, your movie blog can have tags for characters, actors, writers, directors, etc. Unlike categories, tags are wholly optional and non-hierarchical.
You can add tags from your WordPress dashboard in Posts > Tags. You can also add them when editing a post by clicking on the gear icon in the top-right of the screen and then navigating to the Tags section.