Sending JSON values to PHP

How do I send values in a JSON array to PHP? Im stuck with how I actually go about making the request to physically post the values to the PHP file.

I have:

 var myArray = ["john","28","theworld","blue"]; //javascript array

 myArray = JSON.stringify(myArray); //to JSON

I understand what to do once the php file has it, so its just the passing.

Many thanks.