Web2 (or Web 2.0) refers to the evolution of the internet that made it more interactive and user-focused compared to the previous version, Web1. Web2 spans from the early 2000s to the present, transforming the internet into a platform for social networks, blogs, web applications, and user-generated content.

Key characteristics of Web2:

Interactivity:
- In Web2, users can actively interact with content. This includes adding comments, likes, creating user-generated content, blogging, and using web applications.
Social Networks:
- One of the key features of Web2 was the rise of social networks such as Facebook, Twitter, Instagram, and YouTube, which allowed users to not only consume content but also create it.
Content Creation Platforms:
- Web2 enabled content creation by all users, not just website owners. Platforms like WordPress, YouTube, and Medium make it easy for users to create and share content.
Data Centralization:
- In Web2, large platforms and companies (e.g., Google, Facebook, Amazon) accumulated vast amounts of user data, enabling personalized experiences but also raising concerns about data privacy.
Web Applications:
- Unlike static web pages, Web2 introduced dynamic web applications (e.g., Google Docs, Gmail) that work directly in the browser, providing desktop-like functionality.
Monetization Through Advertising:
- Most Web2 services are free for users but are monetized through advertising. This led to a “pay-with-data” model where users trade their personal data for free services.

Examples of Web2 technologies:

AJAX (Asynchronous JavaScript and XML): A technology that allows creating dynamic web pages that can update data without reloading the entire page.
RSS: A way to subscribe to content (e.g., news, blogs) that is updated in real-time.
Social Media and Web Platforms: Platforms like Facebook, Twitter, YouTube, Wikipedia, and Medium are examples of Web2 websites where users create and interact with content.

Advantages of Web2:

Ease of Interaction: Users can easily share information, comment, and create content without needing technical skills.
Rich User Experience: Web2 apps like Google Docs or Slack work directly in the browser, offering functionality and convenience.
Wide Content Creation and Sharing Opportunities: Anyone can become a blogger, YouTuber, or author without needing to build their own website.

Disadvantages of Web2:

Centralization: Control over data and services is concentrated in the hands of large companies, raising concerns about data privacy and monopolization.
Privacy Issues: Due to the extensive data collection, many Web2 platforms face criticism for violating privacy and misusing personal information.
Platform Dependency: Users become reliant on specific platforms and may lose access to their content if the service shuts down or changes terms.

Web2 compared to Web1 and Web3:

Web1: The original version of the internet, which was mostly static. Users could only view content but not interact with it. It was essentially an internet of documents.
Web3: The next phase of internet development focused on decentralization. In Web3, users own their data and content, with blockchain and cryptocurrencies playing a key role in enabling decentralized applications.

Conclusion:

Web2 has become the foundation of the global network we use today, with a vast array of interactive and personalized web services. However, its central issue lies in the over-dependence on large corporations and centralized platforms, a challenge that Web3 aims to address.