The "s" letter is absent in getElementById, because it returns a single element. Frequently asked questions about MDN Plus. And here is the related JavaScript code. childNodes returns nodes: Element nodes, text nodes, and comment nodes. The callback must return a truthy value to indicate a matching element has been found. How can I remove a specific item from an array? You say you quote QuirksMode, but I can't find the original text there, and I'm curious what the differences are. The children property and the childNodes will have the main floor to express the heredity. The id must be unique. Use one of the firstChild, childNodes.length, children.length property to find whether element has child or not. As well as. The children return all child Element nodes of a . The results wouldn't include any span or p elements that have the class We will also see how to extract an individual element from the top and bottom lists. It has the ID, but the element itself could be a