Tags were keywords used within Habbo which players could define themselves with. They were visible on the Home page (before they were removed) and in the Inf-O-Matic, when the user was clicked. Players could write tags to remember someone, interests, hobbies or something, or to describe their personality, and were added by going to "My Page" on the Habbo Home page.
Other players were able to search tags, to find things they have in common, an effective way of finding friends in the Client.
How To Add Tags
With the removal of Habbo Home Pages, the ability to tag a character was also disabled. However, room and group tagging is still available.