The quotation of a currency pair usually consists of two prices. The lower price (bid) is the price at which a market maker is willing to buy the first currency of a pair. The higher price (offer) is the price at which a market maker is willing to sell the first currency of a pair. The spread is the difference between the two prices. For example if the quotation of EUR/USD is 1.2025/1.2028, then the spread is EUR 0.0003 (or 3 pips).