ABSTRACT
This chapter discusses some facts about the A Programming Language (APL) work environment and its management. APL has but one rule governing the order of function execution within APL expressions. The resulting simplicity is especially important because APL has many primitive functions. APL variables are given values by assignment, which is symbolized with a left-pointing arrow. APL functions that require two arguments are called dyadic functions. There are many dyadic functions, but there are many other APL functions that have only one argument; these are called monadic functions. Because there are many primitive functions in APL, many of the function symbols serve "double duty" and signify a monadic or dyadic function according to context. A great strength of APL is that many functions that take scalars as arguments can also take vectors as arguments; the function is applied element wise and the result is a vector. The chapter also presents an overview of the key concepts discussed in this book
