ES_7_includes.js

// ES 7

var fruits = ['mango', 'jack fruit', 'banana' ]
fruits.includes('mango') // true

fruits.includes('orange') // false


// Earlier

var fruits = ['mango', 'jack fruit', 'banana' ]
fruits.indexOf('banana') // returns 2 - index of the array

fruits.indexOf('orange') // return -1 means value is not available in array