Displaying text is a fundamental part of programs because the user will not know what is going on if a program does not display anything on the screen. Most things that you do in a program are displayed on the screen. This includes giving the user instructions, math calculations, or anything else.
There are three commands that are used for displaying text:
The first two commands are for the home screen and the third command is for the graph screen. The fourth command is unique unto itself because it can not only display text on the home screen, but also pause the program until the user resumes it again.
The things that you can display include: text (the text needs to be within quotes), numbers, variables, or expressions. When displaying a variable the current value of the variable will be used, while the expression will be evaluated before it is displayed.
There are certain advantages and disadvantages to each command, and there are also certain situations where each command should be used. You should experiment with the commands to become familiar with them.