What is Blockchain? Blockchain is a decentralized, distributed ledger technology. Tat records transactions securely and transparently across a network of computer. Uses of Blockchain * Cryptocurrencies (e.g., Bitcoin, Ethereum) * Smart Contracts (self-executing agreements) * Supply Chain Management Identity Verification * Decentralized Finance (DeFi) How Blockchain Works * The block is added to the blockchain through consensus. * Valid transactions are grouped into a block. * A transaction is initiated and broadcast to the network. * The transaction is complete and permanently recorded. * The network nodes validate the transaction. Key Features of Blockchain - Security – Uses cryptographic techniques to ensure data integrity and prevent tampering. - Decentralization – No single authority controls the data. - Immutability – Once a block is added, it cannot be changed, ensuring a permanent and reliable transaction history. - Transparency – Transactions are publicly recorded...

  Role of Cryptocurrency in the Modern World Cryptocurrency plays a significant role in various industries, finance, and global economies. Blockchain & Smart Contracts Digital Identity & Security – Cryptos help secure personal data and prevent identity theft. Automation of Agreements – Ethereum and other blockchains enable self-executing smart contracts without middlemen. Supply Chain Transparency – Companies use blockchain to track products and reduce fraud. Investment & Wealth Storage High-Growth Investment – Many investors trade cryptocurrencies like stocks for potential high returns. Digital Gold (Bitcoin) – Bitcoin is often called "digital gold" because it's used as a store of value and hedge against inflation. Diversification – Institutional investors use crypto to balance traditional portfolios. Role in the Future Economy Tokenization of Assets – Real estate, stocks, and commodities can be tokenized for easy trading. Metaverse & Web3 – ...

  Second World War (1939–1945) From September 1, 1939, to September 2, 1945 . It was fought between the Allies (led by the USA, USSR, UK, and China) and the Axis Powers (led by Germany, Italy, and Japan). Causes of war - Rise of Fascism – Dictators like Hitler (Germany) and Mussolini (Italy) promoted aggressive nationalism. - Treaty of Versailles (1919) – Harsh penalties on Germany after World War I fueled resentment. - Invasion of Poland (1939) – Germany invaded Poland on September 1, 1939 , leading Britain and France to declare war on Germany. - Failure of the League of Nations – The international organization was too weak to stop aggression. - Expansionism – Germany, Japan, and Italy invaded other countries to gain territory. End of the War and Consequences - Defeat of the Axis Powers – Germany and Japan surrendered in 1945. - Creation of the United Nations (UN) – Formed to prevent future wars. - Cold War Begins – The USA and USSR became superpowers, leading to a long ...