The price really depend on the bahavior of the buyer and the seller, this is how we detemined demand and supply affects also the price of bitclin. In the future the price of bitcoin will surely go even higher since the demand for this are continue to increase.

The answer is rather simple and it lies in basic economics:scarcity, utility, supply and demand. The combination of two elements: scarcity and utility, creates value by which price is determined based on the market’s supply and demand.
Bitcoins supply is limited. There are currently just over 16.6 million Bitcoin in circulation and the maximum is capped at 21 million. This set cap is well known, making its scarcity transparent. Bitcoin also has undeniable utility even when compared to other, more recent crypto currencies. There is no other digital currency that is more widely used and integrated at this moment. However, Bitcoin's value can not be reduced to just one element or feature. Many aspects of cryptocurrency contribute to its usefulness and offer advantages over traditional paper money and its accompanying systems.

"Everything is worth what its purchaser will pay for it" - Publilius Syrus, (fl. 85–43 BC)

I don't know actually the right thing why is that bitcoinvalue determined. But all I have to know is that because of the user or the number of persons who are using it. The value of bitcoin depend on the demand of the usage or the number of transactions by the users eavh time. The more users I think the high the value.

Certain things that affect the price of Bitcoin are of course, for example Bitcoin will be produced in a limited number, the maximum number of Bitcoins that can be produced in the world is limited to 21 million. There is no limit to the price increase or decrease in Bitcoin, there is no upper and lower limit as in central markets, because it is an anonymous digital currency, decentralized, and Bitcoin's transfer is very easy. I think all of this determines the price of Bitcoin.

I think it's very simple.The answer to this question is rather simple and it lies in basic economics: scarcity, utility, supply and demand.
By definition, if something is both rare (scarce) and useful (utility) it must have value and demand a specific price, with all other things being equal.
Take gold, for example. Why does gold cost as much as it does? Put simply, it is relatively expensive because it is rare, hard to find and limited in supply (scarcity). Gold also has some uses to which consumers derive satisfaction from (utility).
The combination of these two elements creates value by which price is determined based on the market’s supply and demand.

It revolves around the basic economic rule of Demand. If more people want Bitcoin, then the price will likely to go up. If comes a time that no one wants to use Bitoin anymore(which I doubt will ever happen) then It will have no value.

There was a famous story that in the past 2 pizzas cost about 10 000 BTC. Now a single BTC can buy you thousands of pizzas.

The price is always combinations between supply and demand. I think the reason for the current spike in Bitcoin price is the increasing interest from institutional players (banks, funds, high net worth individuals). Since there is so much money out there - the price still can go up once the big guys will get more confident.

As Bitcoin is "young" investment assets, the price of it is strongly affected by news, especially about banning the crypto in some countries (as it was with ICOs in China) and so called "whales", who can manipulate large amounts of bitcoins. And of course, by number of miners, users and hash rate.

You could say there is a starting price since miners consumer a lot of electricity to mine a Bitcoin. That starting price would be the electricity consumed. After that it's basically offer and demand.