Nasdaq Level 2 Totalview - Provides data on all orders made on Nasdaq, NYSE, ARCA & NYSE American issues tradthrough the Nasdaq exchange.
Views:
Level 2 - Shows only the top price level (bid and ask) for each participant (market maker/broker).
Totalview - The full order book for all market participants on the Nasdaq exchange. Includes every single quote and order at every price level for stocks.
Totalview Aggregated - The aggregate of each market participant at each price level. All orders from each broker at a given price level are combined and shown as a single record (total quantity and number of orders at a price level).