Snapshot quotes provide an "Instantaneous" quote and will not stream on your trading platform. Real time quotes provide a constant stream of live, updated quotes on your trading platform. Both, however, will provide the NBBO (National Best Bid and Offer). See also: What is meant by US Securities Snapshot & Futures Value Bundle? and How can I obtain real time US option and stock quotes? For additional information, see US Reg NMS Snapshot Market Data Service in the MEXEM Knowledge Base.