If you use the default Finder tags, like Red, Orange, Blue, etc, and want to name them something that is more helpful, go to Finder, Preferences, Tags. Then Control+Click on a tag and choose Rename. Not only will the tag names show up in file information, but you can search for them in the Finder by tag name, or tag:name to only see files with that tag.
Mac Video Tutorials and Tips for Apple Users
