Chapter 4. Introduction to Variables and Parameters

Table of Contents
4.1. Variable Substitution
4.2. Variable Assignment
4.3. Bash Variables Are Untyped
4.4. Special Variable Types

Variables are how programming and scripting languages represent data. A variable is nothing more than a label, a name assigned to a location or set of locations holding an item of data, in computer memory.

Variables appear in arithmetic operations and manipulation of quantities, and in string parsing.