In addition Buterin wrote about bitcoin-related topics for other publications, including "Bitcoin Weekly". Bitcoins can be stored in a bitcoin cryptocurrency wallet. It allows trading between USD currency and bitcoin cryptocurrency. The bitcoin blockchain is a public ledger that records bitcoin transactions. Additional Hive plugins support querying of the Bitcoin Blockchain. A network of communicating nodes running bitcoin software maintains the blockchain. Elliptic curve cryptography is used by the cryptocurrency Bitcoin. Bitcoin Cash is a cryptocurrency that is a fork of Bitcoin. Andreessen is a proponent of Bitcoin and cryptocurrency. The MIT Digital Currency Initiative funds some of the development of Bitcoin Core. CoinDesk is a news site specializing in bitcoin and digital currencies. In September 2019 the exchange began trading of bitcoin futures. The IQ tokens are intended to be exchangeable for Bitcoin. The two researchers based their suspicion on an analysis of the network of bitcoin transactions. Draper is a major proponent of Bitcoin and decentralization.