A cryptocurrency is a software object with units or “tokens” that can be transferred securely and verifiably from one owner to another. Transactions are recorded in a public, widely distributed database (a “blockchain”). The transfer verification mechanism is cryptographic. It employs a mathematical protocol for authenticating each transaction. The designers of the software object intend it to be used as a medium of exchange, or currency. Hence, cryptocurrency.
Bitcoin was the first decentralized cryptocurrency, introduced in 2009. Many imitators followed – there are now thousands of cryptocurrencies. CoinMarketCap, self-described as “the world’s most-referenced price-tracking website for crypto assets,” counted 4,377 on March 17, 2021.
Over the years, Bitcoin has developed a somewhat tarnished reputation. Traffickers used it to buy and sell drugs on Silk Road – an online black market. Hackers dealt in Bitcoin when extorting payment to remove “ransomware” from hijacked computers and computer systems.
Recently, however, Bitcoin and cryptocurrencies more broadly have moved closer to the mainstream. Prices in dollars for Bitcoin are available on Google Finance and Yahoo Finance. Major banks JPMorgan