jquery/learn.jquery.com — pull request #251 by carterteddy (2013-02-19 03:58:12+00:00)
Title: Some mistake is appeared in "join" section

console.log( myArray.join() ); // "hello,world,!"
console.log( myArray.join("") ); // "helloworld!"

myArray.join() without any args will return "hello,world,!"