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What is the MOOD system?
The MOOD system is a way of displaying the user's current "mood" when posting a comment. It is a way to help improve communication on the site. In addition, artists can get people's overall mood of their work of art by the mood tallies on a deviation.
While composing a comment or reply you can select a mood via the list of emotions represented in the right of the comment window. Each emotion has subsections that you can select by clicking the "more" option next to it.
Presently, some of the emoticons that are used in the MOOD system are not in the Emoticon Legend, so they cannot be used in comments.