Multi-currency transactions simply mean transactions that are performed through one system under various types of currencies. Normally, a merchant can only accept trading in their local currency (if you’re doing business in the USA, you’re usually only allowed to use USD as your main unit of currency).
In order to do business with foreigners and perform cross-border transactions, merchants must connect with a multi-currency payment gateway such as Octalas. Doing so, merchants can send and receive international payments hassle-free and increase their conversion rate, because their customers won’t have to worry about converting their currencies whenever they want to purchase an item from the merchant’s site.