This document provides instructions for calculating the area of rectangles and polygons made up of rectangles. It defines area as the space a shape takes up, measured in square units. The key formula provided is that the area of a rectangle equals its length multiplied by its breadth. Several examples are given of using this formula to find the areas of individual rectangles and composite shapes by splitting them into rectangles and adding the individual areas. The document encourages practicing calculating areas of various rectangle shapes.