At The Market

It's a way of purchasing a stock. Whatever.com is volatile. On any given day lately, it trades between $18 and $20. You have no idea if this thing is going to go to $40 or $4, but you want to roll the dice and own it. You want it now. Right now.

So you call your broker and you instruct her to purchase 1,000 shares of whatever.com at the market. The broker has a screen in front of her, with a live feed of market prices. She tells you that the market price is $18.38 at this moment, and that's the price at which you've just bought whatever.com. You bought it at a price that was at the market.