A: "Real time" foreign exchange rate data is normally used in currency trading, where "buy" and "sell" offers are placed in real time, and remain valid for a very short time (often only for a handful of seconds) within the system in which they are made. This high-frequency data may also include bad quotes and sudden peaks which may not be meaningful beyond the short time during which they are valid.
The Currency System family of products and services focuses on public and official reference rates, as they are used for accounting, e-commerce, expense management, etc. These rates are usually carefully filtered and published about once a day by various institutions, which are supported by the Currency System software and services.
If you need to access "real time" trading data, this probably means that you engage in currency trading, i.e. that you work with a trading platform which by definition also provides real time prices for use within that platform. In that case, only those rates would be meaningful to you.
If you do not buy or sell currencies directly, then you probably mean to use "official", "information" and "reference" rates from one or more providers of your choice, as supported by Currency System, rather than "real time" rates.