NEM (XEM), which stands for New Economy Movement, is a dual-layer blockchain that is written in Java and launched in 2015. The NEM mainnet supports multiple ledgers and has a NEM Smart Asset system, where nodes on the NEM blockchain process API calls. Its native currency is XEM, is 'harvested' using its POI (Proof-of-Importance) algorithm. The 'importance' of NEM users is determined by the number of coins they have and the number of transactions associated with their wallet. NEM also has an encrypted P2P messaging system, multisignature accounts, and an Eigentrust++ reputation system.