confusion over simple variable declaration jQuery “$variable” vs javascript “var”

Question

I have this simple ghost text implementation:

HTML code:

Answer 1

When storing a jQuery selection in a variable, it's common practice to add a $ before the variable name like this:

var $banner = $('#banner');

It's not necessary to include the dollar sign — var banner = $('#banner') would work just as well. However, the dollar sign reminds you that the variable holds a jQuery selection and not just any value like a number or a string.