Bitcoin is useful as it is fast, safe and cheap. Has very less transaction cost and transfer is fast without any amount limitation. It is digital currency so no need to carry any cash more and can use to by stuffs online. No bank involvement or any other third party. It gives great opportunity to invests money in to make more profit.
because it is easy to access and it is accessible for all kind of people in the world, and it has also a good price in the market now thats why many of us like it so much . and one thing we can earn it anonymously thats good for the people who wants it. and it is now being recognize in many countries that is why it is good.