What is React?
Developers use React to build both individual UI components and whole UIs. This includes everything from assembling visual elements to binding data to them and specifying the logic governing how they behave. One of the most important aspects of React is how it handles state changes.
To achieve this, React uses a feature called Virtual DOM, which is just a copy of the real DOM tree that lives in memory. Whenever a change happens in the actual DOM, React will first update its Virtual DOM, then it will render the corresponding JSX to the real DOM. This means that React is able to avoid expensive DOM manipulation, which is the main cause of slow web applications.
Another reason why React is so fast is how it allows engineers to track state and pass information between components. This is typically done through a state container such as Redux or MobX, which provide a centralized state machine that updates state and enables developers to make components more dynamic. This approach helps to prevent re-rendering of the same component in response to small changes, and it also reduces the amount of state that needs to be saved in the browser.