NEO is a platform based on a blockchain. Blockchains are the backbone of many cryptocurrencies, and Neo is both a blockchain platform and a recognized virtual currency. It is designed to be decentralized, which is the case with most other cryptocurrencies. However, it is also designed to be scalable – an area where some virtual currencies have experienced issues. It is written in C# and is most popular in China. The NEO community also permits more than this one currency to be used in transactions, with a second currency known as GAS also in use.