Basically, think of Bitcoin as gold. There is a finite amount of coins (I think the Documentary said something like 21 million TOTAL).
So, like any other precious resource the more that are bought and coveted the higher the price. Pretty simple really.
Note: if you are interested in the Bitcoin documentary I watched (which I found fascinating) you can rent it on iTunes. The title is Banking on Bitcoin.
A bill to amend Japan's Banking Act has finally come to fruition, recognizing Bitcoin and other cryptocurrencies as legal tender. The bill has far-reaching repercussions for the digital currency world as well as the way that cryptocurrencies can be traded and exchanged. The Banking Act was modified after a long process of debate and dialog which saw proponents of digital currencies arguing on their behalf. Now, after months of discussion, the bill has come into effect as of the beginning of April.
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