jQuery Method Chaining

jQuery object methods typically also return a jQuery object, which enables the use of method chains:

$('div.test')
  .on('click', handleTestClick)
  .addClass('foo');

This line finds all div elements with class attribute test , then registers an event handler on each element for the “click” event, then adds the class attribute foo to each element.

Certain jQuery object methods retrieve specific values (instead of modifying a state). An example of this is the val() method, which returns the current value of a text input element. In these cases, a statement such as $('#user-email').val() cannot be used for chaining as the return value does not reference a jQuery object.