In the words of Martin, he is more leaning to the techno-cultural side of the phenomenon, nut sufficiently covered by the otherwise very good wikipedia-entry. At present He sees five characteristics of the Web 2.0 infrastructure, or Web 2.0 applications:

The Web as a Platform

Web 2.0 sees the Web as a platform, rather than just a collection of websites.

• In Web 1.0, people mainly used web browsers to visit and read websites.
• In Web 2.0, the Web can be used by different devices, applications, and services, such as mobile phones, televisions, search engines, and computer programs.
• Web 2.0 applications can provide information without necessarily showing a traditional web page.
• The “client” can be a browser, a background computer program, or even a person who creates and shares new content.
• Information can be exchanged and reused through technologies such as XML.

Web 2.0 turns the Web into a platform where different devices, programs, and people can create, share, and use information.

Point of Presence

A Point of Presence means having a presence on the Web where people or programs can access and share online services and information.

The idea of using the Web has changed over time:

• Web 1.0: People mainly visited websites to read information.
• Web 1.5: Websites such as Amazon and eBay became more interactive. Users could search, buy, sell, and interact.
• Web 2.0: Users become much more actively involved in the online environment. They can create, share, and interact with content.

The Web changed from a place we simply visited into an interactive environment in which we participate.

Microcontent-Based

Web 2.0 is based on microcontent, which means small pieces of information or content that can be easily shared, combined, and reused.

Examples include:

• Blog posts
• Comments
• Tags
• Photos
• Short videos
• Tweets/posts
• Reviews

Instead of thinking of the Web as a collection of separate pages and documents, Web 2.0 sees it more like a constantly changing cloud of information.

This makes the Web:

• Open – information can be accessed and shared.
• Decentralized – information does not come from one central source.
• Bottom-up – ordinary users can create content.
• Self-organizing – content can organize itself through tags, links, ratings, and user activity.

Web 2.0 is made up of small pieces of content that users can create, share, connect, and organize.

Second-Order Content / Metacontent

Web 2.0 often takes content from different sources, processes it using computers, and then reuses or combines it in a new way.

For example:

Information from several websites → collected by an application → processed → combined → presented to users in a new form.

This is sometimes called second-order content because it is content created from other content.

For example, a website might collect information from different sources and display it together rather than creating all the information itself.

Web 2.0 can take information from many places, process it, combine it, and create new useful information from it.

The Metaweb

The idea of the Metaweb is closely related to the Semantic Web.

The goal is to make information on the Web easier for both computers and humans to understand, connect, and organize.

Web 2.0 combines things such as:

• Social networking
• Blogs
• Wikis
• Tags
• User-generated content
• Online communities

Users can add tags to content. These tags help connect related information.

For example, someone might tag an article with:

Technology → Web 2.0 → Social Media

These tags help people and computer systems understand how different pieces of information are related.

Web 2.0 also allows users to collect and organize information according to their own interests.

In simple words:

The Metaweb connects information from different sources and helps both people and computers find, understand, organize, and use that information.