Value refers to relative light and dark in a sample. A series of steps of value has a beginning and an end. Value is first and most easily understood as a series of steps from black to white. White is the highest possible value. Middle grey, the midpoint between black and white, is a middle or medium value, neither dark nor light. Black is the lowest possible value. But value is not just a graduation between white and black, it also includes colour graduations from light to dark.

Harmony brings together a composition with similar units. If your composition was using wavy lines and organic shapes you would stay with those types of lines and not put in just one geometric shape.

Circle, square, and triangle are the three basic shapes used in design. Perhaps the most familiar shape is the square (and rectangle). Paper is rectangular. Most text blocks are square or rectangular. While you may encounter printed projects cut into other shapes, most circles, triangles, and freeform shapes in printed materials are found on the page within the graphics or in the way the elements are placed on the page.