Web3, also known as Web 3.0, represents the next generation of the internet. It aims to decentralise power and give users more control over their data and online interactions. Unlike the current Web 2.0, which is dominated by centralised platforms, Web3 leverages blockchain technology, decentralised finance (DeFi), and smart contracts to create a more open, secure, and user-centric internet. 

Web 2.0 is characterised by centralisation, where control is concentrated in the hands of large corporations. Users rely on intermediaries such as social media companies, cloud service providers, and financial institutions to interact online. These intermediaries control data, manage digital identities, and often monetize user interactions, leading to concerns about privacy, security, and data ownership. In contrast, Web3 is decentralised, with control distributed among users through blockchain technology. Web3 aims to provide more privacy, security, and control over personal data and digital assets. By leveraging decentralised networks, Web3 eliminates the need for intermediaries, allowing peer-to-peer interactions and enabling users to have greater control over their online presence. 

The internet has undergone significant transformations since its inception, evolving through several distinct phases:

- Web 1.0: The early static web, characterised by read-only websites with limited user interaction.

- Web 2.0: The dynamic, social web that introduced interactive content, social media, and user-generated content, allowing users to create, share, and collaborate through platforms like Facebook, YouTube, and Wikipedia.

- Web3: The next generation of the internet, aiming to decentralise power and give users more control over their data and online interactions by leveraging blockchain technology, DeFi, and smart contracts. 

Decentralised Applications, or dApps, are applications that run on a blockchain or peer-to-peer network. These applications operate without a central authority, offering greater security and transparency. Examples include decentralised exchanges (DEXs) and blockchain-based social networks. 

Decentralised Finance (DeFi) refers to financial systems that operate without traditional intermediaries. DeFi platforms enable peer-to-peer financial services, such as lending, borrowing, and trading, through decentralised protocols. 

Smart contracts are self-executing contracts with the terms directly written into code. These contracts automatically enforce and execute agreements when predefined conditions are met, eliminating the need for intermediaries. 

Blockchain technology provides a secure and transparent ledger for recording transactions and data. Each transaction is verified by a network of nodes (computers), ensuring that the data is immutable and tamper-proof. This decentralisation eliminates intermediaries and allows for peer-to-peer interactions, which are fundamental to Web3.