In forex, the Bid price is the price that a trader is willing to sell a currency pair for. The Ask price is the price that a trader is willing to buy a currency pair at.

The Bid price is always smaller than the Ask price.

For example, if a forex trader believes that the EURUSD will appreciate in price then he will buy the currency pair at 1.15290 so he can benefit from the rally.

On the other hand, if a trader thinks that the EURUSD will fall in price, then he will sell the Eurodollar for 1.15200, so he can profit from the decline.