Classification of Variables

The Bash interpreter has two operation modes: interactive (shell) and non-interactive (scripting). Variables solve similar tasks in each mode. However, the contexts of these tasks are different. Therefore, there are more features to classify variables in Bash than in other languages.

Let’s simplify the terminology for convenience. It’s not entirely correct, but it helps avoid confusion. When we talk about scripts, we use the “variable” term. When we talk about shell and command-line arguments, we use the “parameter” term. These terms are often used synonymously.