Terminal

Terminal/Console

Execution environment for applications.

Exposes text buffer. Only one application runs in foreground (this application "owns" keyboard/mouse).

Shell

Application.

Uses terminal, exposes OS functionality for user (via commands). Allows configuration of execution environment (via variables)

Environment variables

Shell utilizes two types of variables:

• local: accessible only via current shell. Not passed to child processes. Created: a=some_value.
  Displayed with set command
• exported: passed to every child process. Created: export a=some_value.
  Displayed with env command