Page 20 - Geektime Blockchain Report
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Cryptocurrencies
A cryptocurrency is a a a a a a a digital asset designed to to to to work as as a a a a a a a a a a a medium of exchange using cryptography to to to to secure the the the transactions and control the the the creation of of of additional units of of of the the the currency Cryptocurrencies
are are classified as as a a a a a a a a subset of of digital currencies
They are also
a a a a a subset of alternative currencies
currencies
and virtual currencies
currencies
Quite a a a a few buyers refer to to cryptocurrencies as a a a a digital version of of gold and turn to it during times of of financial crisis At the the moment there are more than 1 000 active cryptocurrencies A decentralized cryptocurrency is produced by the entire cryptocurrency system collectively at at at a a a a rate that is is is defined when the system is is is created and which is is is publicly known In centralized banking and economic systems such as the Federal Reserve System corporate boards or governments control the supply of currency by printing units of of of fiat money or or demanding additions to digital banking ledgers In the case of a a a a a a decentralized cryptocurrency companies or governments cannot produce new units and have not provided backing for other firms banks or or or corporate entities that hold asset values measured in it thus far Most cryptocurrencies are designed to decrease production of the currency gradually placing an ultimate cap on the total amount of currency that will ever be in in circulation mimicking precious metals The total cryptocurrencies market cap continues to to to grow and has recently surpassed $176B in October 15 2017 setting a a a new record During October the market cap dropped to $140B While there were 2 main decreases
in in in market cap during 2017 - due to the Bitcoin fork and the shift in in in China’s regulation in in in September The general trend in 2017 that can be seen from the graph is a a a a tremendous rise (660%) from the the beginning of the the year to October In other words despite market volatility there is considerable growth in the market Mining
The primary purpose of mining is to to allow the blockchain network to to reach a a a a a a a a a secure tamper- resistant agrment (known as “consensus”) Thus
the safety integrity and balance of ledgers or or record keeping is maintained by a a a a community of mutually distrustful parties referred to as miners: members of the general public using their computers to help validate and timestamp transactions adding them to the the ledger in in accordance with a a a a a timestamping scheme This enables the ability to to come to to a a a consensus in an environment where neither party knows nor trusts each other Cryptocurrency mining is is called this way because it resembles the the mining of other commodities: It requires exertion and it slowly makes new currency available at a a a a a a a rate rate that resembles the rate rate at at at at which commodities like gold are mined from the ground Miners are paid through a a a a combination of Bitcoin’s
block block rewards and transaction fees When a a a a a block block is discovered the discovering miner is is is rewarded a a a certain number of bitcoins which is agreed-upon by everyone in in the the network This is is still the the majority of miners’ earnings Also the the miner is awarded the the fees paid by users sending transactions Both are an an incentive for for miners to pay for for the mining process's electricity and hardware costs Mining
is intentionally designed to be resource-intensive and difficult Individual blocks must contain a a a a proof of of work work to be considered valid This proof of of work work is is verified by other computers each time they examine a a a block 20 





















































































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