What's the key difference between HTMLCollection and NodeList?
The key difference is that an HTMLCollection is live, meaning it automatically updates when the underlying document changes, while a NodeList is usually static (with some exceptions). Additionally, NodeList can contain any node type (elements, text nodes, comments), while HTMLCollection contains only element nodes. In modern JavaScript, NodeList provides forEach() method support, making it easier to iterate over, while HTMLCollection requires conversion to an array or traditional for loops.