Can you please tell the difference between
lets say that you do this
var myel = this.el; // here what you have is the html element, //you will be able to access(read/modify) the html //properties of this element,
var my$el = this.$el; // you will have the element but //with all of the functions that jQuery provides like, //hide,show etc, its the equivalent of $('#myel').show(); //$('#myel').hide(); so this.$el keeps a reference to your //element so you don't need to traverse the DOM to find the // element every time you use it. with the performance benefits //that this implies.
one is the html element and the other is the jQuery object of the element.