Cryptocurrency is a digital currency. it is also called a virtual currency. it is a digital asset that handles its transactions using cryptography,cryptography is used impenetrably and confirms the transactions. In many countries, cryptocurrencies are used as alternative currencies. Bitcoin was added in 2009 as the first decentralized cryptocurrency. After that, many different cryptocurrencies came onto the market. These are usually known as Altcoins. These currencies use decentralized management as a counterweight to centralized digital money and central banking systems. Distributed management uses Bitcoin’s blockchain transaction database like a paid ledger. An encryption device generates decentralized cryptocurrency at a predefined price, which is communicated to the public. In centralized banking and the Federal Reserve System, boards of directors or governments manage the granting of currency through printing units of cash, and the exchange is carried out with digital bankbooks. However, in a decentralized cryptocurrency, companies or governments cannot produce new entities or provide support to various companies, banks, or companies that hold an asset. Satoshi Nakamoto Group created the underlying technical gadget for decentralized cryptocurrencies. Almost a thousand cryptocurrencies were created by September 2017, most of them comparable to Bitcoin. In cryptocurrency systems, security, integrity and general ledgers are maintained with the help of a team of mutually suspicious parties known as miners, whereby the general public is validated by the use of their computer systems and timestamp transactions are maintained by specific timestamp scheme. Miners, in order to preserve the security of a cryptocurrency ledger for economic reasons, most cryptocurrencies are constantly minimizing the production of currency, capping the entire amount of currency in circulation and mimicking valuable metals. Unlike ordinary currencies, which are held via currency institutions, such as holding cash in stock, cryptocurrencies are difficult to seize by law enforcement. This issue is due to the use of cryptographic technologies. Law enforcement officials faced this trouble in the Silk Road case, in which Ulbricht’s Bitcoin stash was “encrypted”. Crypto-currencies like Bitcoin are pseudonyms, although add-ons such as Zerocoinhave been suggested to provide authentic anonymity.