Blockchain is a kind of wallet which was discovered only for Bitcoin transactions as bitcoin is the first digital currency which can be traded in online.  But now-a-days Bitcoin, Ether, Bitcoin Cash can be traded by blockchain.
Like paper money and gold before it, bitcoin and ether allow parties to exchange value. Unlike its predecessors, it is digital and decentralized. For the first time in history, people can exchange value without intermediaries which translates to greater control of funds and lower fees.

Blockchain is connecting the world to the future of finance. It is the most trusted and fastest growing crypto company. They are helping millions across the globe – from single individuals to the largest institutions. It is an easy and safe way to access crypto-currency. Through the use of block chain technology, Blockchain is revolutionizing the $14T financial services industry. Blockchain has raised over $70 million in funding from leading investors including Light-speed Venture Partners and Google Ventures.