ABSTRACT
This chapter presents some key concepts and the basic techniques needed in order to use S language; understanding them will lead quickly to good use of S. Fundamental to the philosophy of S is the uniformity of expressions and data objects. The value of any expression, however complicated, is an object. This includes anything from simple arithmetic expressions to high-level statistical functions. So far as the language is concerned, any expression can appear as an argument to an operator or function. Of course, a particular function may generate an error if it cannot interpret the argument sensibly. S provides an integrated environment for data analysis, numerical calculations, graphics and related computations. The S language is the medium through which all user computations and programming take place. The S language includes operators for the usual arithmetic and logical operations. These compute on all the data values in their operands.
