#!/bin/bashecho helloecho $?    # Exit status 0 returned because command executed successfully.lskdf      # Unrecognized command.echo $?    # Non-zero exit status returned because command failed to execute.echoexit 113   # Will return 113 to shell.           # To verify this, type "echo $?" after script terminates.#  By convention, an 'exit 0' indicates success,#+ while a non-zero exit value means an error or anomalous condition.