Are BID and ASK the minimum and maximum?
So in your screenshot, someone or some group of someones is willing to buy 3,000 shares at $3.45, and someone or some group of someones is willing to sell 2,000 shares at 3.88. Without getting in to the specific mechanics, you can place a market buy order for 10 (or whatever number) shares and it will probably transact at $3.88 per share because that's the lowest price for which someone will currently sell their shares. As a small fish, you can generally ignore the volume notations in the bid/ask quotes.
"You're confusing a specific visual representation of the top bid & ask orders selected from the order book with the actual ""top of the book"".  ""Top"" in the sense of the ""top of the book"" is a ranking (by order of ""best"", different for bids vs. asks) and not meant to be strictly a visual positioning on a page or screen. The data in the visual representation comes from the top of the order book (the best bids, and the best asks), but that visual representation is choosing to present it in a specific way. Think of the ""book"" as the model, the abstract collection of outstanding bid and ask order data.  When people talk about the ""top of the book"", they're talking about the best bids (higher being better), and the best asks (lower being better). The visual representation above is but one possible way to render a tip-of-the-iceberg view of the best orders in the ""book"".  The advantage of that particular visual representation is that one can see the asks & bids converging towards the center.  The spread is visible as the difference between the two middle elements – being the lowest row in the blue ""Asks"" area, and the highest row in the green ""Bids"" area. The up-arrow they had included in the ""Asks"" area was perhaps meant to provide a clue about how the data was sorted contrary to expectations of descending order of ""bestness"", and/or to imply there is further depth to the book data in the indicated direction. If the bids & asks had been oriented side-by-side instead, they might have chosen to represent it as below, re-arranging the rows in the ""Asks"" in the opposite order (i.e. in the order you had expected) so that the ""bests"" are both in the top row:" I can often get the option at [a] price [between bid and ask] The keyword you use here is quite relevant: often. More realistically, it's going to be sometimes. And that's just how supply and demand should work.  The ask is where you know you can buy right away. If you don't wanna buy at ask, you can try and put a higer bid but you can only hope someone will take it before the price moves. If prices are moving up fast, you will have missed a chance if you gambled mid-spread. Having said that, the larger the spread is, the more you should work with limits mid-spread. You don't want to just take ask or bid with illiquid options. Make a calculation of the true value of the option (i.e. using the Black Scholes Model), then set your bid around there. Of course, if not only the option but also the underlying is illiquid, this all gets even more difficult. The Bid price is simply the highest buy price currently being offered and the Ask price simply the lowest sell price being offered. The list of Bid and Ask prices is called the market depth. When the Bid and Ask prices match then a sale goes through. When looking to sell you would generally look at both the Bid and Ask prices. As a seller you want to be matched with the Bid price to get a sale, but you also need to check the current list of Ask prices. If the price you want to sell at is too high you will be placed down the Ask price list, and unless the price moves up to match your sell price you will not end up selling. On the other-hand, if your price to sell is too low and in fact much lower than the current lowest sell price you may get a quick sale but maybe at a lower price than you could have gotten. Similarly, when looking to buy, you would generally also look at both the Bid and Ask prices. As a buyer you want to be matched with the Ask price to get a sale, but you also need to check the current list of Bid prices. If the price you want to buy at is too low you will be placed down the Bid price list, and unless the price moves down to match your buy price you will no end up buying. On the other-hand, if your price to buy is too high and in fact much higher than the current highest buy price you may get a quick purchase but maybe at a higher price than you could have gotten. So, whether buying or selling, it is important to look at and consider both the Bid and Ask prices in the market depth. There are usually so many different options around for the same stock that some are rarely traded. Especially if the price has moved since the option was issued, nobody might be interested in that particular option at that price anymore. So the asking price might be something that someone asked for ages ago and that is much higher than anyone would reasonably pay today.  With a bid of $20 and an ask of $30, nobody is trading, but the value of that option is somewhere between $20 and $30. If the value is below $25, someone will notice your $25 bid and sell. The price is moving higher so by the time you enter your order and press buy, a new buyer has already come in at that time and taken out the lowest ask price. So you end up chasing the market as the prices keep moving higher. The solution: if you really want to be sure that you buy it and don't want to keep chasing the market higher and higher, you should put in a market order instead of a limit order. With a market order you may pay a few cents higher than the last traded price but you will be sure to have your order filled. If you keep placing limit orders you may miss out altogether, especially if the price keeps moving higher and higher. In a fast moving market a market order is always best if your aim is to be certain to buy the stock. "When people talk about ""the price"" of a stock, they usually mean one of the following: Last price:  The price at which a trade most recently took place.  If someone sold (and someone else bought) shares of XYZ for $20 each, then until another trade occurs, the last price of the stock will be quoted at $20. Bid price: The highest price at which someone is currently offering to buy the stock. Ask price: The lowest price at which someone is currently offering to sell the stock. As you can see, all of these are completely determined by the people buying and selling the stock." The purpose of a market order is to guarantee that your order gets filled. If you try to place a limit order at the bid or ask, by the time you enter your order the price might have moved and you might need to keep amending your limit order in order to buy or sell, and as such you start chasing the market. A market order will guarantee your order gets executed. Also, an important point to consider, is that market orders are often used in combination with other orders such as conditional orders. For example if you have a stop loss (conditional order) set at say 10% below your buy price, you might want to use a market order to make sure your order gets executed if the price drops 10% and your stop loss gets triggered, making sure that you get out of the stock instead of being stuck with a limit order 10% below your buy price whilst the stock keeps falling further. The Bid price is simply the highest buy price currently being offered and the Ask price simply the lowest sell price being offered. The list of Bid and Ask prices is called the market depth. When the Bid and Ask prices match then a sale goes through. When looking to sell you would generally look at both the Bid and Ask prices. As a seller you want to be matched with the Bid price to get a sale, but you also need to check the current list of Ask prices. If the price you want to sell at is too high you will be placed down the Ask price list, and unless the price moves up to match your sell price you will not end up selling. On the other-hand, if your price to sell is too low and in fact much lower than the current lowest sell price you may get a quick sale but maybe at a lower price than you could have gotten. Similarly, when looking to buy, you would generally also look at both the Bid and Ask prices. As a buyer you want to be matched with the Ask price to get a sale, but you also need to check the current list of Bid prices. If the price you want to buy at is too low you will be placed down the Bid price list, and unless the price moves down to match your buy price you will no end up buying. On the other-hand, if your price to buy is too high and in fact much higher than the current highest buy price you may get a quick purchase but maybe at a higher price than you could have gotten. So, whether buying or selling, it is important to look at and consider both the Bid and Ask prices in the market depth.