Advanced React, Chapter 5: Memoization with useMemo, useCallback and React.memo

Chapter 5 of Advanced React by Nadia Makarevich — documenting my read-through as part of my dev journey. In this one: useMemo, useCallback, and React.memo — what they actually do, and why memoizing everything doesn't help. Pardon my English mistakes along the way — this is a learning process, not a polished tutorial.