just to clarify level 2. it will only indicate the highest bid and/or lowest offer for each Market Maker ID. you may see NITE bid at .115 for 5000 shares but......... A) they are obligated for AT LEAST 5000 shares but they COULD be there for any amount up to 99,999 shares and you wouldn't know that unless they wanted to show their actual size . B) just because you see NITE at .115, if they get hit and move away there could still be orders at NITE for .114 or .113 etc.