Shell scripting concepts covered in this lesson:

• Pseudocode and pseudocoding.

• Special variables created by the shell including UID.

• How to store the output of a command in a variable with command substitution.

• The if statement.

• The id command.

• The whoami command.

• How to read help and man pages.

• Command options, order, and conventions.

• Conditionals, operators, and expressions.

• The [[, [, and, test shell builtins.

• The command separator.

• Exit statuses.

• Piping output to the less pager.

• Executing commands as root with the sudo command.

• Using the su command to switch users.

• Sanity and “idiot” checking.