What is the difference between real time and snapshot quotes?

Background

IBKR offers eligible clients the option of receiving a real-time price quote for a single instrument on a request basis. This service, referred to as “Snapshot Quotes” differs from the traditional quote services which offer continuous streaming and updates of real-time prices. Snapshot Quotes are offered as a low-cost alternative to clients who do not trade regularly and require data from specific exchanges1 when submitting an order. Additional details regarding this quote service is provided below…

Global Snapshot is a market data service that allows a user to request snapshot real-time price quotes for a single instrument on a request basis from available exchanges worldwide. This service, referred to as “Snapshot Quotes”, differs from the traditional quote services which offer continuous streaming and updates of real-time prices…

Orders are executed at the National Best Bid and Offer (NBBO), which represents real-time price quotes, irrespective of whether the client elects to subscribe to real-time market data.  Orders are handled in this manner for both live and paper trading accounts…

IDEAL FX real time quotes are provided free of charge on accounts in most regions of the world. It is not possible to disable them…