Miscellaneous properties and functions

These utility methods do not fit neatly into the preceding categories, but are often very useful when writing scripts using jQuery.

Properties of the jQuery object

Property	Description
$.support	Return a map of properties indicating whether the browser supports various features and standards

Arrays and objects

Function	Description
$.each(collection, callback)	Iterate over collection, executing callback for each item
$.extend(target, addition, ...)	Modify the object target by adding properties from the other supplied objects
$.grep(array, callback, [invert])	Filter array by using callback as a test
$.makeArray(object)	Convert object into an array
$.map(array, callback)	Construct a new array consisting of the result of callback being called on each item
$.inArray(value, array)	Determine the position of value in array or return -1 if value is not in array
$.merge(array1, array2)	Combine the contents of array1 and array2
$.unique(array)	Remove any duplicate DOM elements from array

Object introspection

Function	Description
$.isArray(object)	Determine whether object is a true JavaScript array
$.isEmptyObject(object)	Determine whether object is empty
$.isFunction(object)	Determine whether object is a function
$.isPlainObject(object)	Determine whether object was created as an object literal or with new Object
$.isWindow(object)	Determine whether object represents a browser window
$.isXMLDoc(object)	Determine whether object is an XML node
$.type(object)	Get the JavaScript class of object

Other

Function	Description
$.trim(string)	Remove whitespace from the ends of string
$.noConflict([removeAll ])	Revert $ to its pre-jQuery definition
$.noop()	A function that does nothing
$.now()	The current time, in seconds since the epoch