Web3 is often contrasted with Web 2.0, where data and content are centralised in a small group of companies, sometimes referred to as "Big Tech". 

Web 2.0 is characterised by social media platforms and services that allow user-generated content but are controlled by centralised entities that monetise user data. In contrast, via decentralised networks, Web3 aims to give users more control over their data and content.

Key features of Web3 include:

• Decentralisation: The use of blockchain technology to distribute data across a network, reducing reliance on central servers and authorities.
• Blockchain and Cryptocurrencies: Web3 utilises blockchain for secure, transparent transactions and cryptocurrencies for digital value exchange.
• Token-based Economics: Integrating digital assets and tokens, representing ownership or access rights within Web3 applications.
• Semantic Web: Enhanced data connectivity and interpretation, allowing machines to understand the meaning behind information.
• Artificial Intelligence: AI and machine learning are used to create more intelligent and adaptive web services.
• Ubiquity: Access to internet content and services from any device, anywhere, and at any time.
• Decentralised Autonomous Organisations (DAOs): Organisations run by code rather than people, where decisions are made collectively by stakeholders.
• Decentralised Finance (DeFi): Financial services that operate without traditional financial intermediaries, using smart contracts on blockchains.

Web3 is still in development, and there isn't a universally accepted definition or fully realised implementation. It is a vision for a more open, user-centric internet that aims to address the limitations and concerns associated with the current centralised web structure. However, critics have raised concerns about the potential for wealth centralisation among a small group of investors, loss of privacy, and the environmental impact of blockchain technologies.