As former MapleLeafs.com columnist David Alter explained in a piece one year ago, the NHL Draft Lottery is comprised of balls marked '1' through '14' with each team having various combinations of those 14 numbers. All told, there are 1001 combinations available between those balls, which are drawn at random. The draw occurs behind closed doors and team representatives -- one from each team eligible in the lottery -- are not allowed contact with the outside world until the lottery is concluded and the results are announced on television.
Prior to 2015, teams further down the standings would only be able to move up a maximum of four selections if they won the lottery.