Why is there a need for using keys in Lists?

Keys are very important in lists for the following reasons:

  • A key is a unique identifier and it is used to identify which items have changed, been updated or deleted from the lists
  • It also helps to determine which components need to be re-rendered instead of re-rendering all the components every time. Therefore, it increases performance, as only the updated components are re-rendered

What is the use of render() in React?

  • It is required for each component to have a render() function. This function returns the HTML, which is to be displayed in the component.
  • If you need to render more than one element, all of the elements must be inside one parent tag like <div>, <form>.

What is a state in React?

  • The state is a built-in React object that is used to contain data or information about the component. The state in a component can change over time, and whenever it changes, the component re-renders.
  • The change in state can happen as a response to user action or system-generated events. It determines the behavior of the component and how it will render.

What is a higher-order component in React?

Higher-order components (HOCs) are a widely used technique in React for applying concepts that involve the component reusability logic. They are not a native part of the React API and allow users to easily reuse the code and bootstrap abstraction.

HOCs are also used to allow simple sharing of behaviors across all of the components in React, adding more advances to the efficiency and functioning of the application.

What is the meaning of create-react-app in React?

The create-react app in React is a simple command-line interface (CLI) that is used in the creation of React applications, which have no build configuration.

All tools are pre-configured when using the CLI, and this allows users to focus on the code more than on dependencies to develop the application.