$() creates a new jQuery object. If you save a jQuery object to a variable it is pointless to create another jQuery object from it, although it still works. You will often see people wrap variables that were previously created as jQuery objects in $() purely due to bad practice and either forgetting it's already an object...or not understanding what they just created in the first place
Perhaps you may have seen
- Code: Select all Expand view
- var $nav = $('nav');
$nav.hide();
Using the $ prefix is a common practice to denote that the variable is a jQuery object for code readability mostly
https://stackoverflow.com/questions/197 ... -use-a-var