Business is often seen as the "bad guy" in environmental matters because people feel that businesses will do anything to make a profit. Unfortunately, this is too often the case. Many business people, in fact, believe that they can’t make a profit and be kind to the environment at: the same time. However, it does not necessarily have to be this way. Using common business strategies, companies have found ways to become environmentally friendly or "green" and increase their profits at the same time. One such strategy that businesses use is known as "product differentiation". This term means that: a company advertised the fact that its products are different from other, similar products. A number of environmentally friendly companies have done this successfully. For example, in marketing their products, organic (有机的) food companies emphasize the organic aspect. That is, they highlight the fact that no chemicals have been used to grow the food, and so it is better for consumers’ health and for the environment. Another "green" business strategy that has been successful is waste reduction. Many companies have considered waste and pollution as a necessary part of the production process. They have done little to prevent either waste or pollution, unless there were laws that forced them to. However, other companies have realized that there are definite advantages to reducing waste and pollution. Less waste and less pollution means a more efficient production process. The 3M Company started a program that rewarded employees for successful ideas about how to reduce waste and prevent pollution last year. This program has helped the company pollute much less and save more than a half billion dollars. What is the passage mainly about