Q:

Why are some variables declared on the same line as others, and most are declared on their own line?

I'm attempting to teach myself JS, and working through trying to build a Blackjack game. I found a site which has a good walkthrough, but quite a lot is confusing me.
Here, they declare Global variables:
var deck;
var burnCard;

var dealer;
var player = new Array(maxSplits + 1);
var curPlayerHand, numPlayerHands;

var credits, defaultBet;
var creditsTextNode, defaultTextNode;

I know/think you can declare multiple variables on one line, like var x, y;
but I'm not sure why it is being used here for some variables but not for others. Why is not possible to put
var = deck, burnCard;

for example?
If I've left out anything important please let me know and I'll include it. Thank you.

A:

For the JavaScript parser it doesn't matter.
Assume someone did it for aesthetic reasons or they were being inconsistent/lazy. 
Lint tools such as JSLint and ESLint will warn you about these inconsistencies.

