Word processor styles are like declarations of a variable in source code: They allow you to save effort by doing work once instead of repeating it each time that you need it.

Most of the time, we're going to be doing expressions inside of some piece of code, inside of a script, which is the Python word for program.

As the Scilab code is put into the exec function, the exit command is concatenated to the end of it so you don't have to rely on the user to input the word exit each time.