What does putting a javascript function inside a '$()' do?

Question

I'm learning some AJAX right now and the jQuery function that is being used to submit the form is wrapped inside $( function() { } ) as so. What does this exactly do?

$(function() {
    $('.error').hide();
    $(".button").click(function() {
        // validate and process form here
    }
});

Answer 1

This is a shortcut provided by jQuery for running code on page ready. It is equivalent to:

$(document).ready(function() {
    ...
});

jQuery will call this function when the page is ready to be manipulated.

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