A market maker is a broker-dealer who facilitates trading in a specific security by displaying bid and ask quotations for a number of shares. Market makers that attempt to provide liquidity to the penny stock market naturally become significant contributors to trading volume. Upon receiving a buy order from a trader, the market maker may either sell shares from its inventory or buy them from the market for onward sale to the investor. Conversely, for a sell order, the market maker may either absorb the shares into its inventory or immediately dump them into the market.