The bid price is what a broker will pay to buy the currency pair from you (the price at which you can sell), and the ask price — also called the offer — is what you must pay to buy it. Prices are always quoted as a bid/ask pair, such as 1.0850/1.0852.
The difference between the two is the spread. You always buy at the (higher) ask price and sell at the (lower) bid price.
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