2. Input and output

By default, once a program starts, it will run its commands without asking the user for information or confirmation. And while it will store the results of any calculations it makes, programs will not inform the user of the results unless a command to do so is included in the software.

We often want the program to wait for user input. After all, word processing software that does not allow the user to type anything in is not useful for much, and nobody would buy accounting software that works out your taxes but does not tell you what is owed.

Input

If you want your program to ask the user for information, you will need to know how to use input commands. In pseudocode, this is done with the RECEIVE...FROM command. For example:

RECEIVE username FROM (STRING) KEYBOARD

This will take a string value the user inputs into the keyboard, and use it to set the value of the "username" variable.

Output

Similarly, when you want your program to provide the user with information, use the pseudocode command SEND...TO. For example:

                     SET myVariable TO 1700
                     SEND myVariable TO DISPLAY

This sets the value of the variable myVariable to 1700, then outputs that to the user.