Definition of Bid Price
What is the "Bid Price"?
The bid price is the highest amount that someone is willing to pay for a stock at that moment.
If you visit quote.yahoo.com and type in a stock, you will be given a "bid price" and an "ask price".

The bid price, as mentioned, is the most that someone is willing to pay for a stock at that moment.
The ask price, on the other hand, is the lowest price that a seller of a stock is willing to accept at that moment.
If you are looking to sell a stock and enter a market sell order, then that order will try to match your sell order with the best available bid at that time.
Example: You bought 5,000 shares of MSFT two years ago and are now looking to sell.
You need the money in order to purchase a vacation property. Time is of the essence, and you need to exit the position immediately.
You log into your online stock broker and notice that the best bid price is $22.05. You enter a market order to sell, and your order is filled within seconds at $22.05.
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