join() - The join() method in JavaScript is used to join the elements of an array into a string. It takes an array and concatenates its elements into a single string..toString() - In JavaScript, the ...

split() - The split() method in JavaScript is used to split a string into an array of substrings based on a specified delimiter and returns the new array. reverse() - The reverse() method reverses the ...

Built-in JavaScript objects and functions are ones you'll use all the time. Here's how to use Object, JSON, String, Math, Date, and console in your JavaScript programs.