What are the differences between referencing an element by ID and by class in JavaScript, and how does it impact the functionality of the code snippet provided?

When referencing an element by ID in JavaScript, you use the getElementById() method, which returns a single element with the specified ID. On the other hand, when referencing an element by class, you use the getElementsByClassName() method, which returns a collection of elements with the specified class name. This impacts the functionality of the code snippet provided because if you are trying to manipulate a single element, you should use ID, whereas if you are trying to manipulate multiple elements with the same class, you should use class. ```javascript // Using getElementById var element = document.getElementById("myElementId"); element.style.color = "red"; // Using getElementsByClassName var elements = document.getElementsByClassName("myElementClass"); for (var i = 0; i < elements.length; i++) { elements[i].style.color = "blue"; } ```