Executing Commands

• Simple Command Expansion:		How Bash expands simple commands before executing them.
• Command Search and Execution:		How Bash finds commands and runs them.
• Command Execution Environment:		The environment in which Bash executes commands that are not shell builtins.
• Environment:		The environment given to a command.
• Exit Status:		The status returned by commands and how Bash interprets it.
• Signals:		What happens when Bash or a command it runs receives a signal.