Single commands can be entered and executed from the Command Line text box at the bottom of the screen. Commands entered in this way do not require the command delimiter @. By default, when you press “Enter”, the command is added to the script window at the cursor current location and executed with any output written to the log window.
You can also enter and edit commands in the script window, but
they will not be executed immediately. Commands entered into the script window
should end with the command delimiter @. You can execute commands from
current cursor position in the script window by using the Run menu, by typing Ctrl+R or by clicking on the execution
(lightning bolt 
) icon on the
toolbar. If none of the commands in the script window are highlighted,
commands are executed from the current cursor position (initially at the top of
the file). If you mark a block of commands, only those commands will be
executed. Commands in the script window can be executed one by one using the
One command step toolbar button 