Understanding is analytical. It is the process of examining the components, parts and processes of a system.

Comprehension is the process of examining and reviewing a system as a whole.

Blackbird (T.merula) is a songbird. I just looked him up: Europe, Asiatic Russia, North Africa. Gets about a bit.

You can watch it.

You can describe its habits.

You can record its song.

You can examine its feathers.

You can examine its skeleton, internal organs and sequence its DNA.

You will then understand everything about Blackbird.

But, until you have stood in a summer’s dawn and listened to Blackbird singing the descant to sunrise, you will not comprehend who and what Blackbird is.