DOM Traversal Methods

Universal: *
All elements.
Examples
1. $('*'): selects all elements in the document
2. $('p > *'): selects all elements that are children of a paragraph element
Description
The * selector is especially useful when combined with other elements to form a
more specific selector expression.
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Chapter 2
XPath Selectors
Modeled after a file system's directory-tree navigation, XPath selector expressions
provide an alternative way to access DOM elements. Although XPath was developed
as a selector language for XML documents, jQuery makes a basic subset of its
selectors available for use in XML and HTML documents alike.
For more information about XPath 1.0, visit the specification at the W3C:
http://www.w3.org/TR/xpath.
Descendant: E//F
All elements matched by F that are descendants of an element matched by E.
Examples
1. $('div//code'): selects all elements matched by that are
descendants of an element matched by
2. $('//p//a'): selects all elements matched by that are descendants of an
element matched by
Description
This XPath descendant selector works the same as the corresponding CSS descendant
selector ($('E F')) except that the XPath version can specify that it is to start at the
document root, which could be useful when querying an XML document.
In example 2, the initial //p tells jQuery to start at the document root and match
all elements that are descendants of it. Keep in mind that if this selector
expression follows a DOM traversal method such as .find(), this syntax will not
select anything because the document root cannot be a child of anything else. Since
jQuery allows free mixing of CSS and XPath selectors, the initial // is redundant and,
therefore, can be omitted.