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More history:

- The first few transactions in 2009 were made by Nakamoto him/herself - Exchange rates published in Oct 2009 : $1 = 1309.03 BTC

- Now 10.000 BTC is worth nearly 3.5 million dollars!

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More history:

- At that time e.g. Wikileaks started to accept donations in bitcoins

- When the exchange rate raised to 12.000 USD/BTC, the China Central Bank banned Bitcoin in China!

- 2014. November: Truecoin

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[*] Picture resource: bitcoin.org

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When we exhange money at e.g. a bank, the anonimity is compromised a bit…

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Remember: bitcoins are inserted in the system by bitcoin miners (they got bitcoins for making transaction blocks).

We have to prove, that our bitcoins are from a mined bitcoin amount!

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Miner software: GUI Miner (https://github.com/downloads/Kiv/poclbm/guiminer- 20121203.exe)

Mining tutorial (HU): https://bitcoin.hu/archivum/bevezeto/banyaszat-az-elso-10- lepes/

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„orphan” blocks : these will be unchained soon and the transactions in it will be released (they will be included in the next few blocks)

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[*] Picture resource: on.tech.eu

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At this point we only know, that if one amount of bitcoins are already spent (=is in an old transaction), the new transaction with these bitcoins are discarded

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When someone starts to make a new block, he/she must be sure, that - All transactions are valid

- The blockchain is valid

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I think this is the real meaning of mining: you mine bitcoins by „mining” an acceptable random nonce for a block…

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[*] Picture ref.: http://optilux.deviantart.com/

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https://bitcoin.org/en/developer-guide#transactions

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