Once the command is accepted the program from the file takes control over the computer. Nothing else is required and the control is returned to the operating system.
Some tasks are much more complicated.
The editing program takes control over the computer and helps you to create a document. Commands to control pico should not be confused with Unix commands which control the operating system. In general each Unix command has three parts surrounded by spaces, as shown below. The remaining two parts may or may not be necessary. The options are additional qualifications for the tasks.