memoizationn

const Something = () => {
  // bla-bla
};

const PureSomething = React.memo(Something);

same as

class PureSomething extends PureComponent {
  render() {
    // bla-bla
  }
}

shouldComponentUpdate lifecycle method

class PureSomething extends PureComponent {
  // re-render component only when the method returns true
  shouldComponentUpdate(nextProps) {
    return nextProps.bla !== this.props.bla;
  }

  render() {
    // bla-bla
  }
}

Same with functional components - custom comparison function

const Something = () => {
  // bla-bla
};

// same as shouldComponentUpdate just in reverse
const customComparisonFunction = (oldProps, newProps) => {
  return oldProps.bla === newProps.bla;
};

const PureSomething = React.memo(Something, customComparisonFunction);

Better use composition to prevent re-renders. Memo is the last resort! Much more robust, predictable, no code polution with chains of useMemo, useCallback.