I was interviewed in Beijing for a machine learning engineer position. The interviewer constantly challenged me about my non-computer science background and asked some very basic computer science knowledge questions. To be honest, I used those techniques a lot when I was doing quant trading and building trading systems. I replied with my own understandings, but my responses were not what she expected. She seemed to be looking for standardized textbook descriptions. What's more, she wasn't very professional regarding some machine learning usages, like how to leverage XGBoost to implement random forests. It was a very bad experience.

What are the definitions and applications of the stack, heap, and other memory areas?