Once upon a time, WordPress.com only provided a Category option.
Categories allowed for a broad grouping of post topics, but when you wanted to describe a post in more specific terms, more categories were required. That led to very long category lists inside the blog and very long lists in Categories Widgets.
So we now have tags, too.
Tags are similar to categories, but they are generally used to describe your post in more detail.
Frequently Asked Questions
We understand that it may be a bit confusing upon first glance (especially to new bloggers), so here are some common questions and answers that may help you out.
Do I have to use tags?
The use of tags is entirely optional (although each post must be attached to at least one category).
Are categories and tags hierarchical?
Categories can be arranged in a hierarchy (see the categories widget to learn more). Tags, however, exist in their own right and have no set relationship to anything else.
Is Tag the same as tag ?
Yes. Capital letters do not change a tag. Blogging is the same as blogging.
Is there a limit to the number of tags I can have?
Yes. While you can technically add as many tags to your post they can seriously hurt your search engine optimization. We recommend no more than 3 or 4 main tags.