Programming Languages: Concepts and Implementation

7.2 Introduction

The type system in a programming language broadly refers to the language’s approach to type checking. In a static type system, types are checked and almost all type errors are detected before run-time. In a dynamic type system, types are checked and most type errors are detected at run-time. Languages with static type systems are said to be statically typed or to use static typing. Languages with dynamic type systems are said to be dynamically typed or to use dynamic typing. Reliability, predictability, safety, and ease of debugging are advantages of a statically typed language. Flexibility and efficiency are benefits of using a dynamically typed language.

The past 20 years have seen the dominance of statically typed languages ...