The following resources are not in any particular order. Use the links to explore JavaScript and jQuery.
You should be able to:
Use Javascript and jQuery selectors to manipulate the HTML DOM, adding, removing, and modifying DOM elements.
Use Javascript and jQuery to get the values of HTML DOM elements.
Understand the different Javascript data types, String, Number, Boolean, Array, Object, Null, Undefined.
Write Javascript functions and call those functions.
Handle HTML and user events.
Use AJAX to GET and POST to URLs, parsing the return data and handling any errors.