Before you ship your product, you should test it to ensure it works under most conditions. Thus NewBASIC provides debugging facilities. You may run your program from within the Builder. The Builder catches run-time errors in your BASIC code and displays the offending line. You can also use the Builder to examine your program's variables, making sure they hold the values you expect. There are various controls allowing you to pause your program at arbitrary places so that you can examine its variables at critical times.