React Performance Optimization: Memoization

A simple component that renders text based on local state
A component that re-renders frequently because its parent re-renders, but its props rarely change
A component that re-renders frequently because its parent re-renders, but its props rarely change would benefit most from React.memo. This is precisely the use case React.memo was designed for - preventing unnecessary re-renders of components when their props haven't changed. The memoization allows the component to skip rendering work when its inputs are the same, which is particularly valuable when the component has expensive rendering logic or many child components.
A form component that updates state on every keystroke
A component that fetches data on mount