A binary bet offers a win or loss outcome, nothing in between.

Binary options are now banned in the EU.

The difference between the price the trader and buy at and the price they can sell at.

Also bid-offer spread. The wider the spread, the more the trader pays, reactively.

Backwardation occurs when a bid price exceeds the ask price.

This usually occurs when stock is suspended or under a share repurchase scheme.

It can also mean that a futures contract will trade at a higher price when it is coming close to expiring.

The opposite of backwardation is known as contango.