Why does Bitcoin change value? Why is the price so volatile?

The value of bitcoin is tied to the laws of supply and demand. In other words, the price of bitcoin is determined by what people are willing to pay for it. If more people want to buy bitcoin than sell bitcoin, then the price will increase. If more people want to sell, the price will decrease. 

Bitcoin’s value can be volatile when compared to more established currencies and commodities. This can be attributed to its relatively small market size, and it means that a smaller amount of money can move the Bitcoin price more significantly. This discrepancy will decrease naturally over time as the currency matures and the market size increases.