Blockchain

Blockchain — What It Is in Simple Terms

Once upon a time, people kept track of debts on clay tablets. Today, blockchain plays that role — only in a digital, highly secure, and much smarter form.

Blockchain is a distributed database — or simply a digital ledger — where all entries (transactions) are grouped into blocks. These blocks are connected in strict order, forming a chain. Each new block relies on the previous one and contains its “fingerprint” (hash).

Key features of blockchain:

• Transparency: everyone can see all the records. Want to check how many bitcoins your neighbor has? Be my guest — no hacking needed.
• Immutability: altering past records is about as easy as rewriting printed books without leaving a trace.
• Decentralization: copies of the blockchain are stored across thousands (or millions) of participants worldwide. No single “boss” can pull the plug or tweak the numbers.

How blockchain works:

1. Several transactions are grouped into a block.
2. The block gets a unique identifier (hash).
3. The block is added to the chain, referencing the previous one.
4. All network nodes update and agree on the new version of history.

Where blockchain is used:

• Cryptocurrencies (Bitcoin, Ethereum, Toncoin — our good old friends).
• Banking and international money transfers.
• Supply chain tracking (from farm to fork).
• Legal transactions (smart contracts without boring notaries).
• Online voting (making sure your vote actually counts).

Advantages of blockchain:

• Security.
• Transparency.
• Fault tolerance.

Disadvantages:

• Slower transaction speeds compared to traditional databases.
• High energy consumption (for some networks).
• Still not a universal tool for every daily need.