What is Kingside?

Kingside refers to the half of the chess board that includes the squares where the king starts the game. It is the right side of the board from white's perspective and the left side from black's perspective. It typically includes the e, f, g, h columns for white and the d, c, b, a columns for black. Kingside can also refer to moves or strategies primarily involving this part of the board, such as a kingside castle or a kingside attack.