Key Differences Between Functional Components and Class Components in React - ReactJS Interview

Functional components and class components are two ways to create components in React. The key differences between them are:

• Functional components are just plain JavaScript functions that take props as arguments and return React elements. Class components are ES6 classes that extend React.Component and use a render method to return React elements.
• Functional components are stateless, which means they don't have access to lifecycle methods or state. Class components, on the other hand, have access to lifecycle methods and can hold state.
• Functional components are simpler and easier to read compared to class components, which can have more boilerplate code.
• Functional components are easier to test and maintain due to their simplicity. Class components can be more complex and harder to test.

When choosing between functional components and class components in React, consider the complexity of your component, the need for state and lifecycle methods, and the ease of testing and maintenance.