No there are technically no coins on the blockchain. As you said there are only tx records and the balance of “coins” is stored in the UTXOs. 
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What keeps track on demand?
Hello MrAndersson. Demand, in this case, is simply how many are currently buying vs. selling. Hi demand is lots of buyers. The value of the bitcoin (like many things) is whatever someone is willing to pay for it.
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So it is basicly based on what ie coinmarketcap calculates?
CMC just tracks the current buying/selling price on exchanges.
Section 7. Transactions and UTXOs question:
Where I’m confused is where I see multiple inputs and multiple outputs. In 5 years I’ve never sent from more than one address in a single transaction, and I’ve never sent to more than one address in a single transaction. I this what the multiple inputs/outputs imply is happening or am I reading that wrong? If so, where/how can you send to/from multiple addresses?
Or is it the case that in every UTXO you have to spend it all, and how the transaction works, for example, is:
Let’s say you have UTXO worth 10 BTC. You want to send 1 BTC. Is it the case that you send all 10, and 9 of those you send back to yourself?
So, I think I’ve thought it through. Each transaction block has multiple inputs over time, which create (add up to) a single UTXO (output). So a UTXO of 5 BTC might have come from 5 separate inputs over time, hence the 5 inputs when spending your 5 BTC UTXO. Am I on the right track?
Even if you sent to a single address you received each time a new UTXO that you can spend. You can verify this in a block explorer.
If you’re using a HD wallet the change is automatically sent to you to a new address. Have you checked how much funds do you have in a particular address where you think you have all your funds?
Yes you must always spend the full UTXO.
No, each time you receive funds you will have a new UTXO available to spend, that you can then use as inputs to a new tx.
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Question about Transactions and UTXOs video
I’ve never used a crypto wallet before, so I got a bit confused about the part of the UTXO that is sent back to you. What I don’t understand is that how is it possible, that the amount sent back to the same wallet, is sent to a different address? Do wallets have multiple addresses?
Towards the end of the video, the blockchain satellite comes up. I looked into the website and also found this video: https://www.youtube.com/watch?v=C1GxxlqRkKQ
Andreas Antonopolous explains that commercial satellite providers lease certain frequencies, and the satellites broadcast on this channel. However, doesn’t that just put control of availability in the hands of the commercial satellite provider?
Ok, so I understand all that. I guess the easiest way to ask my question is; what scenarios (aside from the remaining BTC after tx and fees getting sent back to you) would cause multiple outputs (and multiple inputs). In the video, there was an example that showed, probably, 8-10 outputs. In what possible scenario(s) would there be that many? Same question for inputs.
The wallet can have an unlimited number of key pairs.
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Personally I think this satellite is more for show. Can’t really send a tx there only sync blocks. Still cool though
The wallet will use as many inputs as it needs to fund the tx. If you have your coins in many tiny UTXOs then a lot of them will be required to be spent as inputs to a new tx.
Outputs are for the most part as regular people use them two (for the merchant and change). You can have a look at some txs from exchanges on an explorer. They usually give you the txid when you withdraw or just look at your address when you receive your funds and you’ll notice there are usually a lot of outputs in a single tx. Exchanges do that to save on fees.
I do not know my binance account private key. I only know the public key where people can send Crypto to me. So when i hear about protecting your private key, i get quite confused. Where do i go to find out what is my private key in my account ?
Do i really need to know it ? How would anyone else knows it if i myself dont know it.
However if what you mean is the back up , like the 12 words you have in enjin wallet. That one i know. Is that considered private key ?
Anyone can advise?
You don’t Binance holds and owns your private key.
You should if you want to control your funds.
Yes the mnemonic is used to generate the master key from common english words based on BIP39 that is used to derive the private keys for your account based on path derivation as described in BIP32.
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A basic question… what happened after bitcoin white paper? was the code uploaded on github simultaneously? and someone else runs it now? is there any kind of authority or developer behind its initial deployment?..
The exchanges where people buy and sell Bitcoin
-https://www.investopedia.com/news/why-price-bitcoin-different-around-world/
The code was first uploaded on sourceforge and later moved to github. I don’t know what was uploaded first the code or the whitepaper. The current Bitcoin core maintainer is Wladimir van der Laan.
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