If you only buy some bitcoin and hold it to make profit in the future, i think, it's not business, but investment. But, i'm not recommended you to invest all of your real money into bitcoin, it's high risk and bitcoin prices are fluctuative. But, if you have an idea, like make good service, e-commerce, and make bitcoin as payment, it's good choice and business. You will be a businessman in the future, and when bitcoin increasing, you will get extra income too.