In Salesforce, there are two types of currency configurations: Basic Currency and Advance Currency (Dated). The difference between using Basic Currency Exchange Rates and Dated Exchange Rates is that the former has no history associated with it. However, when your org makes changes to a Dated Exchange Rate, the history is preserved for tracking. This is especially helpful when exchange rates fluctuate significantly.
When a change is made to the Basic Exchange Rate, there’s no history logged about the previous rate. This change affects all opportunities, forecasts and other amounts that use the current conversion rate; something which can significantly affect profit projections based on opportunities stored currently in the system. This is more likely to have a major impact on large, multi-national companies than on small businesses.
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