What is Cryptocurrency?
A cryptocurrency is a digital or virtual currency that is meant to be a medium of exchange. It is quite similar to real-world currency, except it does not have any physical embodiment, and it uses cryptography to work.
Because cryptocurrencies operate independently and in a decentralized manner, without a bank or a central authority, new units can be added only after certain conditions are met. For example, with Bitcoin, only after a block has been added to the blockchain will the miner be rewarded with bitcoins, and this is the only way new bitcoins can be generated. The limit for bitcoins is 21 million; after this, no more bitcoins will be produced.
What exactly is Cryptocurrency?
Benefits of Cryptocurrency
With cryptocurrency, the transaction cost is low to nothing at all—unlike, for example, the fee for transferring money from a digital wallet to a bank account. You can make transactions at any time of the day or night, and there are no limits on purchases and withdrawals. And anyone is free to use cryptocurrency, unlike setting up a bank account, which requires documentation and other paperwork.
International cryptocurrency transactions are faster than wire transfers too. Wire transfers take about half a day for the money to be moved from one place to another. With cryptocurrencies, transactions take only a matter of minutes or even seconds.
What makes Cyptocurrencies special?
What is Cryptography?
Cryptography is a method of using encryption and decryption to secure communication in the presence of third parties with ill intent—that is, third parties who want to steal your data or eavesdrop on your conversation. Cryptography uses computational algorithms such as SHA-256, which is the hashing algorithm that Bitcoin uses; a public key, which is like a digital identity of the user shared with everyone; and a private key, which is a digital signature of the user that is kept hidden.
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Cryptography in Bitcoin Transactions
In a normal bitcoin transaction, first, there are the transaction details: whom you want to send the bitcoins to and how many bitcoins you want to send. Then the information is passed through a hashing algorithm. Bitcoin, as mentioned, uses the SHA-256 algorithm. The output is then passed through a signature algorithm with the user’s private key, used to uniquely identify the user. The digitally signed output is then distributed across the network for other users to verify. This is done by using the sender’s public key.
The users who check the transaction to see whether it’s valid or not are known as miners. After this is done, the transaction and several others are added to the blockchain, where the details cannot be changed.
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