The High Court is the essence of order and the opposing court to the Dark Court. It was one of the two original courts which resided in Faerie. The Dark Court left Faerie to live among humans, and the High Court stayed.
The High Court is viewed as holding itself apart from events that don't involve themselves or don't harm their Court. Their ruler is the High Queen, Sorcha, The Unchanging Queen and Logic.
The High Court is emotionless and controlled. Members of the High Court don't live among mortals, but rather exist in the "otherworld" known as Faerie. They are practical to the extreme.
It is revealed Sorcha and the High Court have a penchant for stealing Halflings and Sighted mortals, a practice the Dark Court is aware of. (Irial hides halflings Ani, Tish, and Rabbit from the High Court.) It's not clear if the seasonal courts are aware of this High Court practice.
The main space of the High Court is the throne room, called the Hall of Truth and Memory. It is the only place in Faerie that doesn't fold under Sorcha's will and is impervious to any magic but its own. When the Dark Court resided in Faerie, inter-court disputes were resolved here. Sacrifices are made here. It has slate-gray stone floors.