Cryptocurrencies are virtual currencies made by individuals across the world. They are digital currencies designed to work as a medium of exchange through a computer network that is not reliant on any central authority, such as a government or bank, to uphold or maintain it.The more people buy these currencies, their prices rise.
Their price can be decided by their makers and can be traded through cryptocurrency exchanges and work just like stock exchanges.
These exchanges are like virtual supermarkets where you can buy any cryptocurrency. You can also redeem them at cryptocurrency exchanges. However, it is important to note that cryptocurrencies are highly unregulated and have higher risk of fraud.

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The first completely functional cryptocurrency surfaced during the financial crisis of 2008, Bitcoin. Since then, Ethereum, Litecoin and Zcash have also been released.
At present, there are more than 18,000 cryptocurrencies in the world (as of March 2022).