The XPointer axes are the same as the XPath axes, and we're already familiar with them. Axes tell you which direction you should search and give you a starting position to search from. Here's the list of possible axes:
The ancestor axis holds the ancestors of the context node. The ancestors of the context node are the parent of context node and the parent's parent, and so forth, back to and including the root node.
The ancestor-or-self axis holds the context node and the ancestors of the context node.
The attribute axis holds the attributes of the context node.
The child axis holds the children of the context node.
The descendant axis holds the descendants of the context node. A descendant is a child or a child of a child, and so on. ...