how to use includes in javascript ? code example

Example 1: javascript string includes

'Blue Whale'.includes('blue')  // returns false

Example 2: includes()

const str = 'To be, or not to be, that is the question.' 

console.log(str.includes('To be'))        // true
console.log(str.includes('question'))     // true
console.log(str.includes('nonexistent'))  // false
console.log(str.includes('To be', 1))     // false
console.log(str.includes('TO BE'))        // false
console.log(str.includes(''))             // true