The document discusses the order of operations, known as PEMDAS or P.E.M.D.A.S. It states that PEMDAS stands for Parentheses, Exponents, Multiplication, Division, Addition, Subtraction and is the proper order to follow when evaluating mathematical expressions. Following PEMDAS is important to get the correct solution and avoid mistakes. Examples are provided to demonstrate how to use PEMDAS to simplify expressions step-by-step.