Types of Forex Currency Pairs: Majors v Minors v Exotic v Currency Crosses

The Majors are typically the most traded currencies, paired with the USD, although some traders may refer to any forex currency pair featuring the USD as one of the majors. The majors are the most actively traded forex pairs which means they most liquid :
EUR/USD, USD/JPY, GBP/USD, AUD/USD
The Minors are normally referring to any of the remaining, non USD forex currency pairs. These slightly less popular pairs often experience more wild swings in both directions due to less liquidity in the market. This also means that their spreads are often wider than those of the majors :
EUR/JPY, EUR/GBP, GBP/CHF, AUD/NZD

What about The Currency Crosses? Once again, the forex currency crosses are just another example of the minors where USD is no longer required to complete the trade. Historically you see, anyone who needed to trade one currency for another would first have to convert their original sum into USD. The currency crosses were first developed to bypass the step of first having to go to USD. While that sounds normal today, at the time this was ground breaking in its business functionality. Examples of a currency cross :
GBP/JPY, EUR/AUD

And finally, sometimes you may also see some of the minors referred to as The Exotics. This just simply means that the currency pair is something that is rarely traded or spoken about in mainstream financial circles. An example of some of the forex currency pairs that could be considered as exotics :
EUR/TRY, CAD/SGD