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What is Blockchain 101: A Definitive Guide

Block chain - Definitive guide
IEEE BLP December 22, 2023

What is Blockchain 101: A Definitive Guide

Blockchain is quickly becoming a buzzword in various industries. This technology was popularised with the advent of Bitcoin in 2008. However, blockchain applications have gone beyond cryptocurrencies and ventured into several real-life uses, with startups receiving up to $5.7 Billion in 2022. The market itself is estimated to grow to $469.49 billion by 2030.

This post provides a comprehensive overview of blockchain technology and its applications, cryptocurrencies and their trading, smart contracts, job opportunities, and more. Learn how to become a blockchain developer or cryptocurrency trader by understanding the following concepts. 

Blockchain as a chain of blocks of data 

What is Blockchain?

Blockchain is a decentralised digital ledger technology that allows secure and transparent transactions without central control. It was introduced in 1991 by Stuart Haber and W. Scott Scorneta as a method of time-stamping digital documents. It was popularised in 2008 with the creation of Bitcoin to implement an immutable transaction ledger. Since then, it has expanded to other uses beyond cryptocurrency.

By creating a network of computers, transactions are recorded and validated in an immutable way. Each block contains a unique hash of the previous block, creating a chain of blocks that cannot be altered without consensus from the network. 

Examples of Blockchain

There are a large number of blockchains in the current ecosystem. Prominent ones include:

  • Bitcoin, the pioneering cryptocurrency and blockchain network;
  •  Ethereum, a versatile platform for decentralised applications and smart contracts; 
  • Solana, a high-performance blockchain designed for scalability.

What are cryptocurrencies?

Cryptocurrencies are digital currencies independent of a central institution and secured by cryptographic encryption. A few well-known cryptocurrencies are Bitcoin, Ether, SOL, BNB and many more.

Bitcoin introduced the decentralised digital token whose transactions would be recorded on the public blockchain, ensuring transparency. Alternatively, Ethereum was designed for validation-of-work payment on the blockchain, which now includes decentralised applications with its native cryptocurrency Ether.

In addition to their role as digital currencies, cryptocurrencies have become a significant asset class for traders and investors. Learning cryptocurrency trading involves understanding how to buy, sell, and exchange these digital assets on various cryptocurrency exchanges while using different trading strategies, technical analysis tools, and market indicators to make informed decisions. 

Cryptocurrency: Bitcoin, Ether, Dogecoin 

Different types of cryptocurrencies

The cryptocurrency market and digital asset space encompass a variety of digital currencies. Different types of cryptocurrencies include Bitcoin, Ether, USDT, etc. 

What is a Blockchain Wallet?

A blockchain wallet is a digital interface for storing, managing, and interacting with cryptocurrencies. It provides users with a unique address on the blockchain network. Security is maintained via a public-private key pair, where the public key is used for transactions and the private key acts as the account password. Commonly used wallets include Metamask, Ledger, and more.

Meta Mask, a prominent crypto wallet

Transactions on Blockchain

Blockchain transactions are verified by a network of nodes using a consensus protocol. This ensures agreement among all nodes on transaction validity. Invalid transactions are rejected, and valid ones are added to the ledger, forming a validated transaction chain. Different blockchains use varying consensus protocols, such as Proof-of-Work in Bitcoin and Proof-of-Stake in Ethereum.

What does Mining Mean?

Mining is a crucial aspect of Proof-of-Work blockchains like Bitcoin. Here, miners solve complex computational problems using computer resources. The first miner to find the solution receives the next block, ensuring transaction validity. Miners are incentivised with rewards, with around $21.61 Million in daily revenue. This ensures their continued participation in the network. 

What Does Hashing Mean?

Hashing is converting data into fixed-size strings using a cryptographic hashing algorithm. It transforms data into a unique hash, where a slight change in the input leads to a different output. This is beneficial for verifying data integrity.

In a blockchain, blocks contain hashes of their data and the previous block’s data, creating a chain. Modifying a block changes its hash, rendering subsequent blocks invalid. This immutability enhances trust and security.

 Smart Contracts

Smart contracts are programs that are executed when specific conditions are met. Depending on the blockchains, they use programming languages like Solidity, Rust, etc., automating processes within the contract.

Smart contracts enhance security, efficiency, and savings. They provide shared information and prevent fraud on the blockchain by eliminating intermediaries.

Smart contracts are utilised in several real-world applications, including cross-border payments, automated asset management, NFTs, etc. 

Decentralised Blockchain Technology

Decentralised blockchain technology eliminates central authority and stores data across multiple nodes, ensuring transparency, immutability, and resilience. This system has several advantages. First, no central storage reduces the risk of failure, enhancing security. Secondly, decentralisation promotes transparency and trust, allowing anyone to access and verify transactions, thereby reducing reliance on intermediaries.

Security Aspects of Blockchain

Blockchains are highly secure because of their architecture. The networks rely on hashing and cryptographic encryption to ensure data integrity. Additionally, transactions have to be verified by the nodes via consensus protocols, ensuring only valid transactions are added, making the blockchain immutable.


It is an open-source blockchain platform maintained by the Linux Foundation. It provides blockchain-based services for enterprises. It promotes cross-industry collaboration by developing blockchains and distributed ledgers, focusing on performance and reliability.

Key frameworks include Hyperledger Fabric and Hyperledger Sawtooth, and tools under Hyperledger include Hyperledger Caliber, Hyperledger Explorer, etc.

Blockchain Platforms

Many platforms provide unique solutions with distinct features. Some of them are:

  • Bitcoin is the pioneering platform for peer-to-peer digital transactions, serving as a decentralised currency. 
  • Ethereum, another prominent blockchain platform, enables smart contracts and decentralised applications with its native cryptocurrency, Ether. 
  • Ripple is a currency exchange network known for its fast and low-cost cross-border payment services.

Ethereum, a prominent blockchain platform 

Blockchain solutions and applications in different domains

Blockchain’s applications in the real world are vast, through which businesses gain enhanced security and efficiency.

  • In finance, blockchain enables secure and transparent transactions like remittances.
  • In Healthcare, the secure sharing of medical records ensures patient data privacy. 
  • Blockchain ensures security and integrity in data management by implementing cryptographic hashing. 
  • The telecom industry uses blockchain for identity management. Decentralised identity systems ensure fraud-proof identity verification.

Market Size

As reported by MarketsandMarkets, the global blockchain market size is estimated to be $7.4 billion in 2022. It is expected to grow to $94 billion by the end of 2027, projecting a Compounded  Annual Growth Rate (CAGR) of around 66% over five years. According to CoinMarketCap, Binance, with $76 billion daily trading volume on the exchange as of August 2022, is currently the world’s largest exchange by cryptocurrency trading volume.

Opportunities in Different Domains

Blockchain technology has opened new jobs, giving rise to roles like blockchain analysts, blockchain developers, cryptocurrency traders, investors, etc. Learning blockchain technology can also open up fintech, banking, and logistics opportunities. Blockchain also continues to be adopted in sectors like healthcare and real estate. With the increasing embrace of blockchain technology, start learning blockchain today to capitalize on the rising demand for blockchain professionals.

Cryptocurrency trading, a feasible job option

Salary and Jobs

Recent reports show that the average fresher’s blockchain developer salary in India is around Rs. 7,26,550 annually.  The salary depends on experience and skills, ranging from Rs 5,00,000 to 30,00,000 annually. Top companies like IBM and Accenture hire blockchain professionals with competitive salary packages. Companies in the Web3 space, such as Chainlink and Polygon, provide highly lucrative salaries in similar ranges to developers.

How To Learn Blockchain

You can learn about blockchain technology from various courses and avail multiple opportunities. These courses will cover topics such as Fundamentals of Blockchain And Cryptocurrency, How To Learn Blockchain Development and How To Become A Blockchain Developer. These also include courses mainly offered by IEEE. Check out some of the courses here


  • Blockchain: An immutable, decentralised ledger of transactions.
  • Cryptocurrencies: Digital currencies that use cryptography for security and blockchain for transaction validation. 
  • Node: A device that participates and maintains a copy of the blockchain. 
  • Decentralisation: Distribution of decision-making across multiple participants rather than a single central authority. 
  • Consensus Protocol: Algorithm used by blockchain to agree on the validity and unanimity of transactions. 
  • Blockchain Wallets: Digital wallets that store and manage cryptocurrencies. 
  • Mining: Addition of new transactions to the blockchain network through computational power. 
  • Web3: Next-generation internet that aims to create a decentralised and user-centric online ecosystem. 
  • Fork: A divergence in the blockchain resulting from a change in the blockchain’s protocol, as approved by the community.
  • Token: A digital asset representing value or utility issued and managed on a blockchain platform. 
  • Smart Contracts: Self-executing contracts with terms directly written into code and executed on a blockchain. 
  • Key: A cryptographic tool used for identification and digital signature verification in blockchain systems. 
  • Gas: A small fee representing the computational effort required to execute transactions or smart contracts on a blockchain. Web3, the future of interconnected web 




  1. What is blockchain?

Ans: Blockchain is a decentralised digital ledger that records data across a network, using cryptography for data validation

2. What is a blockchain used for?

Ans: Blockchain is used for cryptocurrency transactions, decentralised applications (dApps), smart contracts, etc.

3. What is Cryptocurrency, and how does it work?

Ans: Cryptocurrency is a type of digital currency. It uses cryptography for security and blockchain for verifying transactions, eliminating the need for intermediaries.

4. What are the four types of cryptocurrency?

Ans: The four types of cryptocurrency are payment cryptocurrencies, utility tokens, stablecoins, and central bank digital currencies.

5. Is cryptocurrency a good investment?

Ans: Investing in cryptocurrency has risks and rewards. It is essential to evaluate the risks before making any investment decisions.

6. How much is 1 BTC right now?

Ans: The value of Bitcoin as of now is Rs 24,51,938. The value fluctuates and is dependent on market conditions.

7. How much is one crypto coin worth in Indian rupees?

Ans: The value of a crypto coin in INR depends on the specific cryptocurrency. You can check out the exact prices here.

8. How much is Bitcoin selling today?

Ans: 1 Bitcoin is selling for Rs. 24,51,938 today. The buying price on exchanges may differ slightly due to the “spread,” which is the exchange’s profit margin. Therefore, the final selling price depends on the specific exchange used for the trade.

9. Why is the value of BTC going up?

Ans: The price of Bitcoin can increase due to various factors, including increased adoption, market speculation, macroeconomic conditions, and global events.

10. What is Ethereum used for?

Ans: Ethereum empowers dApps and smart contracts, fostering decentralised development and deployment whilst eliminating intermediaries.

11. Will Ethereum go up in 2023?

Ans: Market, adoption, and technology impact Ethereum’s price. Speculation on price increases relies on these factors.

12. Is Ethereum stronger than Bitcoin?

Ans: Both Ethereum and Bitcoin possess unique strengths and weaknesses. Their value and utility may vary over time.

13. What is a smart contract with an example?

Ans: Smart contracts are automated financial contracts where the conditions are written in code and executed only when the terms are met. Example: An agreement which transfers an asset from one wallet to another after a particular time

14. What is a smart contract vs blockchain?

Ans: Smart contracts are self-executing agreements written in code. Blockchain is a distributed ledger that records transactions. Smart contracts are executed on blockchain networks.

15. What are smart contract types?

Ans: Smart contracts are categorized by their complexity and functionality. They can be financial, exchange, or governance contracts written in languages like Solidity by developers.

16. What is a blockchain wallet?

Ans: A blockchain wallet is a software application allowing users to securely store, manage and withdraw their digital assets and cryptocurrencies.

17. Is it safe to use a blockchain wallet?

Ans: A blockchain wallet is safe to use if the user follows the required security measures of the wallet.

18. How can I find my blockchain wallet?

Ans: You can find your blockchain wallet by navigating to the specific wallet and logging in with your user credentials. Is Ethereum stronger than Bitcoin?.

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