I found a button in the google cloud front end that uses this syntax and I was just wondering what it is all about... Thanks for the input!
I love design patterns and have been getting more into web development lately so forgive me if this is a really basic question!
That's just the element inspector of your browser. It means in the browser's Javascript console, you can now type $0 and get an object that refers to your currently highlighted element. It's a handy shortcut for directly debugging DOM elements interactively.
It's not HTML, it's not even actually part of the web page, it's not specific to that button, it's not a design pattern.
