Hockey standings run on points, and the standard rec and youth system is 2 points for a win, 1 for an overtime or shootout loss, and 0 for a regulation loss. The overtime loss (OTL) is why a hockey table has three result columns instead of two: losing in overtime still earns something, and a team that keeps games close gets rewarded for it.
Some competitions use a 3-2-1-0 system instead — 3 points for a regulation win, 2 for an overtime or shootout win, 1 for an overtime or shootout loss — which is what the IIHF uses for its championships. It makes every game worth the same 3 points, where 2-1-0 hands out 3 for an overtime game and 2 for a regulation one.
Many beer leagues have no overtime at all and let a regular-season game end tied. A tie is worth 1 point each, the same as an overtime loss, so many leagues simply count it in the same column.