For better performance you can use direct functions like $.ajax() than $.get(), $.getJSON(), $.post() because the last ones are shortcuts that call the $.ajax() function.
I've never written an app where the overhead of $.getJSON has been any kind of bottleneck.
Don’t forget about using .data() function to store stuff for your elements
How is this a performance tip?
Sometimes it’s faster to use $(window).load() than $(document).ready() because the last one occurs before all the DOM elements are downloaded
Say what?
If you want to save some bits on compressing your js plugin – replace the $(document).onready() event
Saving bits! The favorite optimization bikeshed of the JavaScript glitterati.
The best way to test a Javascript code is the human way :D But, you still can use some automated tools like Selenium, Funcunit, QUnit and QMock to test your code
I hope this is a joke.
The new HTML 5 standard comes with a lighter DOM structure in mind
What?
When styling a few elements it is best to simply use jQuery’s css() method, however when styling 15 or more elements it is more efficient to append a style tag to the DOM.
Or, if you're worried about performance and reusability, you could use classes and use addClass and removeClass.