double-double

In-N-Out's double cheeseburger. Though it sounds like it should be a quadruple, the menu clearly explains that this means double meat and double cheese.

I've heard but never tested that they'll gladly make you a 3x3 or 4x4 (even stranger names, but you get the idea) if you ask for it. In fact, there's a whole world of unlisted items available for purchase that just aren't listed on the menu. The only ones I can remember right now are animal style, wishburger, and grilled cheese.

These undocumented interfaces to In-N-Out were discovered by somebody who hex dumped one of their franchises. Such reverse engineering is now illegal, due to the DMCA.

Many vendors don't feel obliged to provide backwards compatibility in undocumented interfaces, so you use them at your own risk. For example, if you become dependent on In-N-Out's grilled cheese, you may find yourself in deep trouble following an upgrade.

A double-double is a basketball term in which a player reaches double figures in two categories (points, rebounds, steals, blocks, assists, etc.). For example, if a player has 10 points and 12 assists, he has a double-double. A small amount of players each year average a double-double, which is pretty impressive. A harder task to acomplish is a triple-double, in which a player reaches double figures in three categories.