The Malaysian Ringgit (MYR) is the official currency of Malaysia.
Melaka, similar to every other place around Malaysia, uses the Malaysian Ringgit or better known as RM (Ringgit Malaysia). Notes come in the forms of RM 1, RM 5, RM 10, RM20, RM50, and RM 100. As for sen (cents), they come in 5, 10, 20, and 50 sen.
When you run out of cash, there are many local and foreign banks / ATMs located in Melaka for you to make cash withdrawals. In addition, currency exchange services are also sometimes available around tourist attractions, so be on the lookout!