Binance Coin (BNB) is a cryptocurrency that can be used to trade on the Binance cryptocurrency exchange and pay fees. As of January 2018, the Binance Exchange was the world's largest cryptocurrency exchange, processing over 1.4 million transactions per second.
As an incentive, Binance Coin users receive a discount on transaction fees on the Binance Exchange. BNB can also be exchanged or traded for other cryptocurrencies like Bitcoin, Ethereum, Litecoin, and others.