What is the difference between these jQuery ready functions?

Question

what is difference between

$(function(){

}); 

and

$(document).ready(function() { 

});

Answer 1

} else if (jQuery.isFunction(selector)) {
    return rootjQuery.ready(selector);
}

From the source

Calling $(document).ready(selector) saves a few if statements.

Although jQuery does cache $(document) internally that might make $(f) faster.

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