Comprehension usually used with of. Knowledge about a subject, situation, etc. Both comprehension and understanding can be used to talk about someone's ability to understand something.
Equipment used for SNF analysis in milk.pptx
Understanding a concept means you get it. The meaning of understanding is a mental grasp : How to use understanding in a sentence.
Or about how something works:
Understanding implies abilities and dispositions with respect to an object. Your understanding might be that your mother will always drive you to school if you miss the bus. Understanding is a relation between the knower and an object of understanding. He noted bond's apparent lack of.
