What is the difference between State and props in React Js ?

Props are shorthand for properties.they are very similar to an argument is passed to a pure javascript function. Props of the component are passed from parent component which invokes component. During a component’s life cycle props should not change consider them as immutable.In React all props can be accessible with this.props.

import React from 'react';
class Welcome extends React.Component {
  render() {
    return <h1>Hello {this.props.name}</h1>;
  }
}
const element = ;

State are used to create dynamic and interactive components in React.State is heart of react component that makes it alive and determines how a component renders & behaves.

// simple state example 
import React from 'react';
class Button extends React.Component {
  constructor() {
    super();
    this.state = {
      count: 0,
    };
  }

  updateCount() {
    this.setState((prevState, props) => {
      return { count: prevState.count + 1 }
    });
  }

  render() {
    return (<button
              onClick={() => this.updateCount()}
            >
              Clicked {this.state.count} times
            </button>);
  }
}

export default Button;