The document discusses the distributive property of multiplication over addition. It provides examples of applying the property to numerical and algebraic expressions. It also identifies common mistakes or "pitfalls" in using the property, such as forgetting to distribute to all terms, distributing to numbers outside of parentheses, or writing the order of terms incorrectly. An analogy using a story about sitting in the front row at a whale show is provided to help remember the rules of the property.