The “Block” in Blockchain⬛

Previously I’ve talked about how the blockchain is a chain of transactions that has taken place in a publicly distributed ledger. Hence the chain⛓️, but what about the “block”? 🟪

Let’s dip our toes in the fountain of knowledge. 📰

A block from the game “Minecraft”

As we’ve mentioned earlier, the blockchain is like a public ledger. A comprehensible way to look at a single block is as a page in that public unchangeable ledger. The same unchangeability exists for a block. 📘

A block is a bundle of transactions. Where the block usually has a set size, but this size can vary between blockchains, this is called block size. There have been huge debates on what the optimal of block size is, however, this is for another time. 😲

There are a few types of blocks: Genesis block, valid block, orphan block

Genesis blocks: The origin block, the first block in a blockchain. After the genesis block is mined the blockchain can start to construct its history of transactions.

Boss baby

The genesis block is very important, because when the genesis block fills up with transaction data, a new block is linked to its state. They are linked through cryptography, most commonly a Merkle tree, which allows the new block to associate a unique hash with the “historic” blocks. 🍼

So, every block that is committed and validated by the nodes to the blockchain has a cryptographic association to all previous blocks, hence a chain.

The current block, or the block where all transactions are recorded right now, has not yet been committed to the blockchain. When it is, it’s filled up and cryptographically connected to the rest of the chain. 🚼

Valid blocks: A valid block are all blocks that has been mined, filled up with transactions, and added to the blockchain via consensus, and exists on every node, and as a result every node has verified it. What allows this block to be validated by all is the hash, or the cryptographic fingerprint of you want. It must be equal on all nodes.✔️

A well-known orphan

Orphan blocks: Blocks that is not a part of the blockchain network. Because new blocks constantly are mined, filled up with records, and then sent to get verified and added to the blockchain, errors may occur. 😥

One of these errors is two blocks may be processed at the same time.

If that happens, one of the blocks must be made an orphan and is not a part of the chronological valid blocks.

This process is carried out by the miners, who through a consensus process chose which block to validate. Usually, it’s the block that has the most amount of history or longest blockchain that is chosen. 🦇


The blockchain starts of with a genesis block, which has no history, because it’s the first block.

Then as the block is filled up with records of transactions, new blocks are mined. 💥

The current block represents what is happening on the network now.

This block contains a cryptographic fingerprint that has a piece of every block before it.

This new block with its unique fingerprint and new transactions is broadcasted to every node on the network, who verify the block, and compares fingerprints of it to make sure they have an identical chronological blockchain stored. 📡

This is confirmed, the block is added to the chain of blocks and can never be changed, a new one is mined, and the process continues. 💯

This was a short summary on blocks!




internet gambler

Love podcasts or audiobooks? Learn on the go with our new app.

Recommended from Medium


Radix Engine and Ledger: The Road to Adoption

UNXD leverages Chainlink VRF for verifiably random reveal of DGFamily Glass Boxes

Remarks on Deschain Fee Model

Revolutionizing the ‘Open Data Economy’ on Blockchain

Defi Wizard — Telegram AMA — February 28

British Blockchain Association Publishes UK Blockchain Roadmap, Ethereum PoS Gets JPMorgan Thumbs…

An picture of an autumn leaf

Get the Medium app

A button that says 'Download on the App Store', and if clicked it will lead you to the iOS App store
A button that says 'Get it on, Google Play', and if clicked it will lead you to the Google Play store
Dimitri Lousteau

Dimitri Lousteau

internet gambler

More from Medium

CryptoMap: One of the biggest NFT collections ever created is about to launch.

Update: RWC 2022 POSTPONED

A Neo N3 NFT Collection: Flamboyant Flamingos

Flamboyant Flamingo