Popular traded currency pairs on Forex are known as Majors. EUR/USD is the most liquid currency pair and among the list of major currency pairs.
There is no formal list of major currency pairs, but directly refers to the six most actively-traded Forex pairs:
AUD/USD – Australian dollar to US dollar
EUR/USD – EURO to US dollar
GBP/USD – British Pound to US dollar
USD/CAD – US dollar to Canadian dollar
USD/CHF – Us dollar to Swiss Franc
USD/JPY – US dollar to Japanese Yen