Here is the visual illustration of the binary tree concepts that I mentioned earlier. It shows the structure of a binary tree, the height calculation, and highlights the recursive nature of computing the height. It also marks the null pointers, helping to clarify the idea of counting them in binary trees.

If you have further questions or would like to delve into additional details, feel free to ask!

Here are 5 related questions that could expand your understanding:

1. How does the time complexity differ for calculating the height of balanced and unbalanced binary trees?
2. What is the maximum possible height of a binary tree with $n$ nodes?
3. Can the recursive height calculation be optimized using dynamic programming techniques?
4. How does the proof of null pointers change for a complete binary tree?
5. How would the calculation of height differ in an N-ary tree?

Tip: When implementing binary trees, consider edge cases such as empty trees and single-node trees to ensure your code handles all scenarios correctly.