What is Blockchain?

Blockchain is a decentralised, secure digital ledger that records transactions across multiple computers to ensure transparency and prevent tampering. Unlike traditional databases, blockchain operates on a peer-to-peer network, using cryptographic security to validate and store information immutably.

This technology powers cryptocurrencies like Bitcoin and Ethereum but is also used in supply chain management, smart contracts, and secure data sharing.

Blockchain works by grouping transactions into blocks, which are verified by a network of computers (nodes). Once verified, the block is added to the chain, creating an irreversible and secure transaction history.

Blockchain is like a digital notebook that everyone can see but no one can secretly change. Imagine a chain of blocks, where each block is a page of records. Once a page is full, it’s locked, and a new one starts – connected to the last. Since copies of this notebook exist on many computers, no one person can cheat or erase history. This technology powers things like Bitcoin, secure contracts, and even tracking products in a supply chain.

An example of a blockchain is Bitcoin, the first and most well-known decentralised digital ledger that records all Bitcoin transactions securely and transparently. Another example is Ethereum, which not only tracks cryptocurrency transactions but also supports smart contracts and decentralised applications (dApps). Other blockchains like Hyperledger and Solana serve industries beyond finance, including supply chain management and gaming

The four types of blockchain are public, private, consortium, and hybrid.

• Public blockchains (like Bitcoin and Ethereum) are open to anyone and fully decentralized.
• Private blockchains (like Hyperledger) are restricted to specific users and controlled by a single entity.
• Consortium blockchains are semi-decentralized, managed by multiple organizations (common in banking and supply chains).
• Hybrid blockchains combine public and private features, allowing controlled access while maintaining transparency.

Each type serves different industries based on security, transparency, and control needs.

A block is locked through cryptographic hashing and consensus mechanisms like Proof-of-Work (PoW) or Proof-of-Stake (PoS).

A cryptographic hash links blocks together, ensuring data integrity and preventing tampering.

Blockchain technology is used in cryptocurrency transactions, smart contracts, supply chain management, healthcare records, voting systems, and decentralised finance (DeFi).

A blockchain wallet is a digital wallet that allows users to store, send, and receive cryptocurrencies securely. Examples include Zypto App wallet, MetaMask, and Ledger hardware wallets.

Blockchain is highly secure due to cryptographic hashing and decentralised validation. However, vulnerabilities can exist in smart contracts or poorly implemented blockchain networks.

Public Blockchains (e.g., Bitcoin, Ethereum) are decentralised, open to anyone, and highly secure.

Private Blockchains (e.g., Hyperledger) are controlled by an organisation and used for business applications.

• Transparency and immutability
• Enhanced security
• Reduced transaction costs
• Faster cross-border payments
• Elimination of intermediaries

•  Scalability issues
• High energy consumption (for Proof-of-Work blockchains)
• Complex implementation for businesses

While blockchain itself is extremely secure, individual wallets, exchanges, and smart contracts can be hacked if they have vulnerabilities. Using secure wallets and strong authentication methods such as a Zypto App wallet helps mitigate risks.

A blockchain explorer is an online tool that lets users search for transactions, view wallet balances, and track block confirmations on a blockchain network.

To become a blockchain developer, start by learning blockchain fundamentals and programming languages like Solidity (Ethereum), Rust (Solana), or Python. Gain experience with smart contracts, decentralised applications (dApps), and blockchain security.

Hands-on practice with testnets, hackathons, and open-source projects will boost your skills. Many developers also take online courses or obtain blockchain certifications.