Introduction Have you ever wondered what are null values in data? Honestly, before diving deep, I assumed they were equal to zero, if I encountered them in numeric columns and if in text columns, simply nothing. As a result, I ended up with mismatched numbers, wrong visualizations. My worst nightmare! I got baffled, but I was sure that this must do something with these null values and I decided to learn more about them and their behavior so I can be confident that the