The goal of this book is to teach you to think like a computer scientist<\/a>. This way of thinking combines some of the best features of mathematics, engineering, and natural science. Like mathematicians, computer scientists use formal languages to denote ideas<\/a> (specifically computations). Like engineers, they design things, assemble components into systems, and evaluate tradeoffs among alternatives. Like scientists, they observe the behavior of complex systems, form hypotheses, and test predictions.<\/p>\n The single most important skill for a computer scientist is problem-solving<\/a>. Problem-solving means the ability to formulate problems, think creatively about solutions, and express a solution clearly and accurately. As it turns out, the process of learning to program is an excellent opportunity to practice problem-solving skills. That\u2019s why this chapter is called, \u201cThe way of the program\u201d.<\/p>\n On one level, you will be learning to program, a useful skill by itself. On another level, you will use programming as a means to an end. As we go along, that end will become clearer.<\/p>\n A program is a sequence of instructions that specifies how to perform a computation. The computation might be something mathematical, such as solving a system of equations or finding the roots of a polynomial, but it can also be a symbolic computation<\/a>, such as searching and replacing text in a document or something graphical, like processing an image or playing a video.<\/p>\n The details look different in different languages, but a few basic instructions appear in just about every language:<\/p>\n input: Get data from the keyboard, a file, the network, or some other device.<\/p>\n output: Display data on the screen, save it in a file, send it over the network, etc.<\/p>\n math: Perform basic mathematical operations like addition and multiplication.<\/p>\n1.1 What is a program?<\/h4>\n