I do so like the shapes in this block and feel pleased that as a newbie I recognise them as triangles and diamonds, please say I am right!
Almost, Margaret. Triangles certainly at the four corners and of course, a square in the center. Those other four pieces (the striped ones) are parallelograms. A rectangle is a parallelogram with four equal angles. So while all rectangles are parallelograms, not all parallelograms are rectangles.