But anyway, I'll explain what Bitcoin is: Bitcoin is two things, I guess. The first being a payment processing protocol much like a bank or paypal where you can transfer value (money) between different people. The reason why Bitcoin is important in this regard is that it solves what is called the 'double-spend' problem which haunts something like paypal by using a public ledger called the 'blockchain' which automatically verifies every transaction made through the network.
The second thing is that, 'bitcoins' are a supposed to be a form of money themselves. The creator(s) of Bitcoin were quite well versed in a school of economics called the 'Austrian School', and one of that schools main arguments is that government should never be allowed to have a monopoly on the issuance of money. They would say that government issued money is prone to inflation, and governments use it as a political tool leading to massive business cycles and such.
Whether people should buy them or not is probably up to them, but I do believe that Bitcoin or something like it, will replace government fiat currency very soon.
Bitcoin Maston Instance