Key Takeaway:
- Blockchain is a revolutionary technology that enables secure and transparent peer-to-peer transactions and data storage.
- Understanding how blockchain works involves a decentralized network of computers validating and recording transactions in a chronological chain of blocks.
- Blockchain technology offers numerous benefits, such as enhanced security, transparency, and efficiency, but it also comes with challenges and considerations that need to be addressed.
Have you ever heard of blockchain and wondered what exactly it is? Well, you're not alone. The term "blockchain" has been thrown around a lot in recent years, often in the same sentence as "cryptocurrency" or "Bitcoin." But what does it actually mean? And more importantly, how does it work? In this article, let’s break down the basics of blockchain and explain its pros and cons.
What is a Blockchain?

What’s Blockchain, photo by Pexels - Tima Miroschinichenko
Blockchain technology allows for the recording and tracking of transactions and assets in a digital ledger. Think of it like a digital notebook where you can record different transactions, but instead of being stored in one physical location, it's spread across a network of computers. Multiple transactions are recorded in each block of the chain; once added, it stays permanent. This creates an unchangeable record of all transactions that have ever occurred on the blockchain.
Blockchains are the technology behind the rise of cryptocurrency, but it's not limited to that. We can use blockchain for many other purposes, such as supply chain management, voting systems, healthcare, and tourism industries. It's a complex technology, but it's also a revolutionary one that can potentially change how we store and share information.
The main use of blockchain technology is to provide a secure and decentralised way to record transactions and track assets. This makes it ideal for a wide range of applications, such as.
- Cryptocurrency: Blockchain technology is the backbone of many popular cryptocurrencies, such as Bitcoin, Ethereum, and Litecoin. It allows for secure, decentralised transactions without a central authority.
- Supply Chain Management: Blockchain technology enables the tracking of goods and materials throughout the supply chain, ensuring transparency and preventing fraud and counterfeiting
- Banking and Finance: Blockchain can speed up and secure financial transactions and reduce the need for intermediaries such as banks.
- Digital Identity: Blockchain can also create secure digital identities for individuals and organisations.
- Healthcare: We can use blockchain technology to securely store, share medical records, and improve the healthcare system’s efficiency.
- Voting systems: We can utilise blockchain technology to guarantee the security and integrity of voting by creating a transparent and verifiable record of all votes cast.
Explaining How Blockchain Works

Explaining How Blockchain Works, photo by Pexels - Olya Kobruseva
So, you know that a blockchain is a digital ledger used to record transactions and track assets, but how exactly does it work?
Series of Blocks That Linked Together
Let's start with the basics. A blockchain is a series of "blocks" linked together in a chain. Each block contains a record of multiple transactions, and every time a new transaction is added to the block, it gets added to the chain and can never be altered or deleted. This creates an unchangeable record of all transactions that have ever occurred on the blockchain.
Nodes on the Network
In a blockchain network, nodes are devices that maintain and update the blockchain. Each node has a copy of the entire blockchain, and when a new block is added, all the nodes on the network must come to a consensus that the block is valid before it is added to the chain. This consensus is achieved through consensus algorithms, such as Proof-of-Work or Proof-of-Stake.
The nodes on the network also play a critical role in verifying and validating transactions, and in some cases, they are also responsible for creating new blocks. The decentralised nature of blockchain technology means that any device can act as a node, and the more nodes on the network, the more secure and resilient the blockchain becomes.
Consensus Mechanism Explained
A popular consensus mechanism is called "proof of work." Bitcoin uses it and works by having the nodes on the network compete to solve a complex mathematical problem. The first node to solve the problem gets to add the following block to the chain, and in return, it gets a reward in the form of Bitcoin.
Another consensus mechanism is "proof-of-stake." Instead of having nodes compete to solve a mathematical problem, in proof-of-stake, a node is chosen to add the next block to the chain based on the amount of cryptocurrency it holds or "stakes." The more cryptocurrency a node holds the better chance of being chosen to add the next block.
Once there's a new block to the chain, it gets a unique "hash", which acts like a fingerprint for that block. If someone were to tamper with a block, it would change the hash of that block, and the hash of every subsequent block would also change. This would be immediately obvious to the other nodes on the network, and nodes would reject the tampered block.
Blockchain Technology Pros & Cons

Blockchain Technology Pros & Cons, photo by Pexels - RODNAE Productions
Blockchain technology has many potential benefits, but it also has some drawbacks to consider. Here are some of the pros and cons of blockchain technology:
Pros | Cons |
Decentralization One of the most significant advantages of blockchain technology is that it is decentralised, meaning there isn’t any central authority controlling it. This makes it more secure and resistant to tampering. | Scalability One of blockchain technology's main challenges is scalability. As the number of users and transactions on a blockchain network grows, it can become increasingly challenging to process them all on time.
|
Transparency
Blockchain technology is designed to be transparent, with all transactions recorded on a public ledger that is accessible to everyone. This can help to increase trust and reduce fraud. | Legality
Blockchain technology is still relatively new, and there is currently a lack of clear regulation around it. This can make it difficult for businesses to know how to comply with laws and regulations. |
Security Blockchain technology is highly secure, thanks to its use of cryptography and the decentralised nature of the network. This makes it an attractive option for a wide range of applications. | Energy consumption Bitcoin and other cryptocurrencies based on proof-of-work consensus mechanisms require a lot of computational power, which in turn consumes a lot of energy. This is an environmental concern and a potential drawback of the technology. |
Efficiency Blockchain technology can speed up and automate processes, reducing the need for intermediaries and making transactions faster and cheaper. | Complexity Blockchain technology can be complex to understand, implement and manage for some people, making it difficult for some businesses to adopt it. |
Immutable Blockchain technology is immutable; once the data is recorded on the blockchain, it cannot be altered or deleted. This creates an unchangeable record of all transactions that have ever occurred on the blockchain. | Lack of standardisation Many blockchain platforms and technologies are available, each with its own strengths and weaknesses. The lack of standardisation can make it difficult for businesses to choose the right platform for their needs. |
In conclusion, blockchain technology is a secure and decentralised way to record transactions and track assets. It has a wide range of potential applications but also has its limitations, such as scalability, lack of regulation, energy consumption, complexity and lack of standardisation. Despite these challenges, many businesses and organisations are exploring ways to use blockchain to improve their operations. However, it's important to remember that blockchain technology is still in its early days, and its potential impact on different industries is yet to be seen.