Distributed Ledger Technology (DLT) - BlockChain

A distributed ledger is a type of data structure which resides across multiple computer devices, generally spread across locations or regions.

Distributed Ledger Technology includes blockchain technologies and smart contracts. While distributed ledgers existed prior to Bitcoin, the Bitcoin blockchain marks the convergence of a host of technologies, including timestamping of transactions, Peer-to-Peer (P2P) networks, cryptography, and shared computational power, along with a new consensus algorithm.

In summary, distributed ledger technology generally consists of three basic components:

• A data model that captures the current state of the ledger

• A language of transactions that changes the ledger state

• A protocol used to build consensus among participants around which transactions will be accepted, and in what order, by the ledger.

A blockchain is a peer-to-peer distributed ledger, forged by consensus, combined with a system for smart contracts and other assistive technologies.

Together, these can be used to build a new generation of transactional applications that establish trust, accountability, and transparency at their core,while streamlining business processes and legal constraints.

With all distributed ledgers, there's an initial record or, in this case, a block, or a genesis block

Each block will include one or more transactions.
Connecting to a blockchain involves people connecting to this distributed ledger via, typically, an application.

So, an example of this would be a wallet.

One person may transfer ownership of a digital asset, like a cryptocurrency, from one person to another,and that asset will move from one person's wallet to another person's wallet,
and then, that transaction will be shown on a blockchain.

So, this distributed ledger transaction, such as a payment, will move from peer-to-peer throughout the network,

and there's no intermediaries, like a bank, or a payment company, to process this transaction.

Can you give an example of a blockchain which has been in production since a few years?

Blockchain is actually best known because of Bitcoin.And Bitcoin's blockchain has been in existence since 2009.
It's a cryptocurrency, but, interestingly, people confuse the two terms.

Blockchain is actually not Bitcoin, or vice versa.
Blockchain is a distributed ledger. The blockchain then tracks various assets, other than cryptocurrencies, such as Bitcoin.
Those transactions are grouped into blocks, and there can be any number of transactions per block. Turns out, nodes or machines on a blockchain network group up these transactions and they send them throughout the network.

The process of blockchains syncing up have to do with a concept of consensus - an agreement among the network peers.

Eventually, each machine has an exact copy of the blockchain throughout the Network.


Smart contracts are simply computer programs that execute predefined actions when certain conditions within the system are met.Smart contracts provide the language of transactions that allow the ledger state to be modified. They can facilitate the exchange and transfer of anything of value (e.g. shares, money, content, property).


Consensus refers to a system of ensuring that parties agree to a certain state of the system as the true state.