Fundamentals of Programming: Debugging
Over the next few chapters you will, no doubt, find several issues with code that you are trying to run. In some cases it won't do exactly what you want it to, in other cases it may break half way through and in many cases when you first start programming it will completely refuse to run! To fix code that doesn't work in the way you want it to is called 'debugging'. If you are used to getting everything right all the time and never making mistakes, you might want to pick another subject. If you get really angry when things don't work as you expect them to, CALM DOWN, or get a bullet proof monitor. Programming is about making lots of mistakes and learning from them, there is nothing to be ashamed of things not working first time.
It just won't run!
When you first start programming the most common problem you'll meet is with code not running at all