JQuery :: How To Assign Function (Call Myclass)

I'm pretty new to Jquery but been using mootools for quite some time now... I just wonder, how could I assign function to jquery? In javascript, we do the regular :
function Myclass() {
//some code here
}
and call the Myclass by:
Myclass();

In mootools:
var Myclass = new Class({
//some code here
});
And call the Myclass by:
window.addEvent("domready", function() {
new Myclass();
});

In Jquery, how would I do that? Is it okay to use the javscript function instead? Or is there a standard way of doing that in jquery?
function Myclass() {
//some code here
}
$(document).ready(function() {
Myclass();
});