Pillows are triangular pieces, the pillow sides refers to the long side and the pillow end refers to the small triangular edges. The cushion and base pieces are both rectangular and fold in the middle. The base piece is slightly thicker than the cushion. The tops of these pieces are on the same side of the connected fabric that allows the fold. The side refers to the thin long side and the end refers to the thin short side. The bottom will be the sides exposed when the cushion or base pieces are folded.