Validation means to check that the data that is entered into the form is correct or not, react-js use bootstrap classes to implement validation practically. Step by Step React JS Validation Process Example1: import { useState } from "react" ; const isEmailValid = ( email ) => {     const emailPattern = / ^ [ a-zA-Z0-9._- ] + @ [ a-zA-Z0-9.- ] +\. [ a-zA-Z ] {2,10} $ / ;     return emailPattern . test ( email );   }; function Formvalidation () {     const [ inputValue , setInputValue ] = useState ( undefined );     const [ error , setError ] = useState ( undefined );     const [ email , setEmail ] = useState ( undefined );     const handleInputChange = ( e ) => {         const value = e . target . value ;       //  setInputValue(value);             // Validate if the input is not empty         if ( ! val...