Reading the BID vs ASK Tutorial (Market Size vs Market Depth)

Auction market → always displays the “best available price” at any given time (aka the BID and ASK) BID = highest price people are willing to pay. Ask = lowest price people are willing to sell at. NBBO “National Best Bid and Offer” shows the highest (BID) and lowest offers (ASK) for a security among all exchanges and market makers. This data may not be sufficiently up to date, so investors may not get the prices they were anticipating upon trade execution, a concern for high-frequency traders “Market size” Indicates how many shares are available at the BID and ASK prices. “Market depth” (Also called level 2 quotes) Indicates nb of shares are available at each and every price that is inf to the BID and suprir to the ASK.