Project planning involves answering two questions. Answering the first question, “What do we need to do?” is generally called requirements gathering. Answering the second question, “How will we do it?” is called designing or specifying (see Figure 3-1). A requirement is a carefully written description of a criterion that the work is expected to satisfy. (For example, a requirement for cooking a meal might be to make inexpensive food that is tasty and nutritious.) Good requirements are easy to understand and hard to misinterpret. There may be different ways to design something to fulfill a requirement, but it should be easy to recognize whether the requirement has been met when looking.
