What is the `String.prototype.includes` method in JavaScript?
Description : `includes` checks if a string contains a specified substring and returns `true` or `false`.
Answer :
`String.prototype.includes` checks if a string contains a specified substring. It returns `true`if the substring is found, otherwise `false`.const str ='hello';
console.log(str.includes('ell'));// true
console.log(str.includes('world'));// false
`Array.prototype.flat` creates a newarraywith all sub-array elements concatenated into it recursively up to a specified depth. It can flatten nested arrays to a specified level.const arr =[1,[2,[3,[4]]]];const flatArr = arr.flat(2);
console.log(flatArr);// [1, 2, 3, [4]]
`Array.prototype.flat` creates a newarraywith all sub-array elements concatenated into it recursively up to a specified depth. It can flatten nested arrays to a specified level.const arr =[1,[2,[3,[4]]]];const flatArr = arr.flat(2);
console.log(flatArr);// [1, 2, 3, [4]]
What is the `String.prototype.bold` method in JavaScript?
`String.prototype.bold` returns a string wrapped inHTML`<b>` tags. Note that this method is deprecated and should not be used in modern applications.const str ='hello';const boldStr = str.bold();
console.log(boldStr);// '<b>hello</b>'
`String.prototype.bold` returns a string wrapped inHTML`<b>` tags. Note that this method is deprecated and should not be used in modern applications.const str ='hello';const boldStr = str.bold();
console.log(boldStr);// '<b>hello</b>'