In the over-the-counter market, the term "ask" refers to the lowest price at which a market maker will sell a specified number of shares of a stock at any given time. The term "bid" refers to the highest price a market maker will pay to purchase the stock.
The ask price, also known as the "offer" price, will almost always be higher than the bid price. Market makers make money on the difference between the bid price and the ask price. That difference is called the "spread."