The Node.previousSibling read-only property returns the node immediately preceding the specified one in its parent's childNodes list, or null if the specified node is the first in that list.
The NodeIterator.nextNode() method returns the next node in the set represented by the NodeIterator and advances the position of the iterator within the set. The first call to nextNode() returns the first node in the set.
The NodeIterator.previousNode() method returns the previous node in the set represented by the NodeIterator and moves the position of the iterator backwards within the set.
The NodeIterator.whatToShow read-only property represents an unsigned integer representing a bitmask signifying what types of nodes should be returned by the NodeIterator.
The NonDocumentTypeChildNode.nextElementSibling read-only property returns the element immediately following the specified one in its parent's children list, or null if the specified element is the last one in the list.
The Page Visibility API lets you know when a webpage is visible or in focus. With tabbed browsing, there is a reasonable chance that any given webpage is in the background and thus not visible to the user. When the user minimizes the webpage or moves to another tab, the API sends a visibilitychange event regarding the visibility of the page. You can detect the event and perform some actions or behave differently. For example, if your web app is playing a video, it would pause the moment the user looks at another browser, and plays again when the user returns to the tab. The user does not lose their place in the video and can continue watching.
A processing instruction provides an opportunity for application-specific instructions to be embedded within XML and which can be ignored by XML processors which do not support processing their instructions (outside of their having a place in the DOM).
The Range.commonAncestorContainerread-only property returns the deepest — or furthest down the document tree — Node that contains both boundary points of the range. This means that if Range.startContainer and Range.endContainer both refer to the same node, this node is the commonAncestorContainer.