Level two is real time bid and ask data with underlying volume spreads between all the MM's that are currently providing for that specified ticker. It is best to have buy and sale times which include volume of the buys to get a better grip on what is actually going on in the L2. Never pay for L2 unless you have the money to spend on something special. L2 is free from TD all you need to do is call them and ask them to activate it for free. Etrade requires 30 trades per quarter to be eligable for their e trade pro program and or have 25k in your account.