Learned how to use a namespace to group a number of functions together even if they don't have any associated data;

Learned how to write an “endless” loop to execute a section of code an indefinite number of times;

Learned how to check numeric input for validity and give the user a reasonable error message if that input is invalid;

Learned how to obtain keyboard input without having to wait for the user to hit the ENTER key;

Learned how to write output on the screen at a particular position;

Learned how to clear the screen or an individual line on the screen;

Learned how to display part of a list on the screen, scrolling the rest of the list on and off the screen as necessary;

Learned how to use the xstring concatenation operator to aid in the formatting of data;

Learned how to compare and sort xstring data without regard for case;

Learned how to print data on the printer, including the use of the “form feed” character to ensure that any further data sent to the printer will start on a new page;

Learned how to delete an item from a list kept in a Vec.