Remembered GIGO
When I studied computer science GIGO was a common term that’s commonly used to nail down into my head that computers are stupid if you write something stupid. GIGO stands for Garbage In Garbage Out which means computers are mere processors that produce appropriate output for the input provided. So if you throw in garbage you are sure to get garbage out. Even to this day GIGO is valid and you cannot throw in anything you want to a computer and expect out something meaningful. It is just that we now have good looking screens to put the garbage in and good looking screens to get the garbage out. 
