A tag is a short label attached to an item to show what it is about or what state it is in. It is like a small sticker on a storage box: one word can help you recognize what is inside.
For example, a task list might use tags such as “Urgent” or “Waiting.” The tag adds a quick clue, but it does not replace the task's name or explain every detail.
Choose a few familiar words and use them consistently. If a tag can be clicked to filter or change something, make that action clear; otherwise, people may think it is a button when it is only a label.