Take something complex, and break it down into smaller, easier to understand pieces.  Each "Chunk" should be = the smallest possible unit of information to explain any topic

"Chunking" is the idea of breaking down a big (hard to understand) concept into smaller pieces.

The idea of "chunking" is used in teaching, and is nicely explained by Dr. Barbara Oakley, University of California, San Diego:  "When you first look at a brand new concept it sometimes doesn't make much sense... Chunking is the mental leap that helps you unite bits of information together through meaning. The new logical whole makes the chunk easier to remember, and also makes it easier to fit the chunk into the larger picture of what you're learning."

Learn more about Chunking