What is "teamchess"

(Tactical) Team Chess is both a game and a sport played by two teams (up to 16 [typically 4-6] players in each team) on a single 8 by 8 classical chess board with standard set of pieces (2×16, Whites and Blacks), using standard (or usual) chess playing rules, while control over the pieces is shared among the teammates who are not allowed to communicate with each other during the play other than via valid moves.