Tags help ensure a particular coworker sees your activity.
Tags are similar to @ replies on Twitter (e.g. @JaneSmith). Tagging a coworker in a newsfeed post, comment, or chat message will instantly notify them about your post, comment or message.
To tag a coworker, type '@'. A list of people in your organization will appear. Keep typing their name and the list will filter down to include possible matches.
You can use tags in almost every part of Arcade. Give it a try!
If you see someone tagged in a post and want more information about them, you can click the tag to bring up a quicklinks menu which shows the person's full name, level on Arcade, and allows you to quickly Recognize or Chat with them. If you're a manager you may have additional options to interact with that person.