my React JS Notes - Hooks
In ReactJS, useState, useEffect, useRef, and similar functions are called Hooks. They are special functions that let you "hook into" React features, like state management and lifecycle methods, from functional components. Introduced in React 16.8, Hooks allow you to use state, side effects, and other React features without writing class components. Other built-in Hooks include useContext, useReducer, useCallback, useMemo,