IntroductionBlockchain's impact on industries is increasing rapidly. The technology has the potential to disrupt all the industries of the modern world with its decentralization and mutual trust behaviour. Einancial services were the early adopters of blockchain, but presently, every industry wants to try this technology. Supply-chain, healthcare, social media, entertainment, energy, gambling, gaming, robotics, analytics, marketing, real estate, retail & ecommerce, education, charity, legal, art and social media industries have their projects already proliferating in the market. The biggest advantage of a distributed ledger is maintaining an unchangeable shared ledger between two firms which gets automatically updated after every transaction.

Fiat currency is money issued by the government and regulated by central banks such as the Reserve Bank of . They are based on a centralized system, which means they are operated by a single entity such as the Reserve Bank of India or the Federal Reserve. These centralized systems, including your bank, handle all your finances, make all transfers, update account tasks, and store all information about "your money."Cryptocurrencies differ from fiat currencies in that they are only available in a digital format and are not controlled by any central authority. This is called decentralization. To understand cryptocurrencies, we need to understand what a decentralized system or a decentralized ledger is.Decentralized ledger explanationLet's start with what is a ledger?A ledger is a written or computerized record of all transactions that have been completed by a business. Usually, it is maintained by a centralized institution, such as the accounting department of a bank or company. In a distributed ledger, there are multiple participants to handle these tasks. When these tasks are distributed to everyone in the network, it is called a distributed ledger. When these tasks are distributed to only certain people in the network, it is called a decentralized ledger. Bitcoin's ledger is a decentralized ledger.Blockchain interpretationA blockchain is a similar database that allows multiple users to record and make changes in it. Once data is entered, it cannot be deleted or changed because it only provides the capability to add data. Data can only be added to the blockchain if a majority of participants provide consensus to confirm its authenticity through a process called "mining." The data (transactions in the Bitcoin blockchain) will be represented as a block in the network. The data is broadcast on the blockchain network and the authenticity of the transaction will be verified using a consensus mechanism. Once the network considers the block to be real, a new block is generated. It is then added to the latest state of the blockchain.In a decentralized system, information is not stored in one place. Each time a new change occurs or a new transaction occurs, the node first validates the transaction and then receives a copy of the new state of the ledger. A full node is basically a device (such as a computer) rather than a human manually performing verification tasks. However, the entire blockchain data is publicly available on the Internet, and anyone can become a node by downloading the same data. All nodes on the blockchain are connected to each other and are constantly exchanging the latest blockchain data with each other so that all nodes stay up to date. They store, disseminate, and preserve blockchain data. So, in theory, a blockchain exists on a node.