As of date we are currently in the second wave of the World Wide Web which is popularly known as “Web 2.0”. After reading several articles about the meaning of Web 2.0 I can say that there is no direct or standard definition for it, although many articles give similar details on its characteristics, technologies, concepts and usage.
According to the Wikipedia page for “Web 2.0” this was how the World Wide Web inventor Tim Berners-Lee described the term “Web 2.0” in a podcast interview. 
"Nobody really knows what it means...If Web 2.0 for you is blogs and wikis, then that is people to people. But that was what the Web was supposed to be all along." 
Referring on the same article, Tim O’Reilly, who is generally credited for coining the term, defined the concept as, “the web as the platform”. 
While in Investopedia Financial Dictionary, the concept of “Web 2.0 does not refer to any technical upgrades to the Internet; it simply refers to a shift in how it is used”.
When looking at the various definitions of Web 2.0 it is imperative to study the evolution of some aspects of the web in order for us to have a clear understanding of the developments in hypertext, hypermedia, interactivity and social media, and try to predict or determine what will be the ultimate manifestation of Web 2.0.
Hypertext, Hypermedia and Interactivity
It is written in Wikipedia that hypertext is the underlying concept defining the structure of the internet.  In effect, though already existing since 1977, hypertext was made famous by the World Wide Web, as stated in Lincoln University Internet Encyclopedia .
Although existing definitions of “hypermedia” vary slightly from hypertext, and may have been used interchangeably, author Ted Nelson – who coined both terms in 1965 – wrote in 1992:
“By now the word "hypertext" has become generally accepted for branching and responding text, but the corresponding word "hypermedia", meaning complexes of branching and responding graphics, movies and sound – as well as text – is much less used.”
Whether both terms are used incorrectly or interchangeably it is undeniable that the development of hypermedia has been a great catalyst for the popular reception of interactive CD-ROMs and the World Wide Web, according to Darren Hughes in his article Taking the "Hype" Out of Hypermedia: A Teaching Tool 
In Clay Carr's article, "Hypertext: A New Training Tool?" (1988) Carr sees the greatest potential for hypertext in data retrieval, in allowing "a user to access information in an associative, intuitive way-without regard for its actual location or for any visible database structure".  The overwhelming growth of the World Wide Web is strong validation of this theory. Cloud computing, touted as one of the technologies to be greatly utilized in Web 2.0, and social media are perfect examples of this purpose.
As indicated by David Lowe and Wendy Hall in their book Hypermedia and the Web, in terms of the current state of hypermedia, we are now at a point where many of the technical limitations associated with handling various forms of media have been removed - at least to a limited extent. Similarly we have begun to develop an understanding of how to manage the various technologies in a reasonably cohesive fashion. But this has lead to the current situation of a hypermedia as a tool for information provision and procurement, rather than the broader concept of a tool for information utilization.
The word "interactive" is often used as a synonym for new media such as the World Wide Web. “Interactivity” on the other hand, as per Denis McQuail, is the ratio of response or initiative on the part of the user to the offer of the source/sender. Several articles supported that the internet is one of the most excellent systems to elicit human interaction. McMillan states that interactivity can occur at many different levels and degrees of engagement and that it is important to differentiate between these levels. User-to-user interaction via the internet; para-social interaction, where new forms of media are generated online; and user-to-system interactivity which is the way devices can be engaged with by a user.
Web applications have become more sophisticated, therefore prompting internet users to upload their own images, documents, audio, and videos online. Considering that the internet has a communication model of many-to-many, rather than the traditional one-to-many, we can say that the chances of reaching other people globally through your uploaded data is immensely huge. Interactivity in the new media has played a big role in promoting liberal democracy and free market in Web 2.0. Sharing the same thought is Paul Graham in his article, “Want to start a start up?”, He believes that the second big element of Web 2.0 is democracy. He says, “We now have several examples to prove that amateurs can surpass professionals, when they have the right kind of system to channel their efforts.”
The rise of social networking sites like Facebook and Twitter changed how we communicate and collaborate, at least to some remote and virtual degree. User-generated content is considered to be one of the highlights of Web 2.0.
In a status report entitled, ”User Generated Content, Social Media, And Advertising” by the Interactive Status Bureau, it was written that, “Social networking is the ultimate manifestation of user generated content, and as such, holds more potential for growth than any other form of content on the Web today.”
But not everyone did not like the outcome of this new model, critics such as Andrew Keen argue that Web 2.0 has created a cult of digital narcissism and amateurism, which undermines the notion of expertise by allowing anybody, anywhere to share and place undue value upon their own opinions about any subject and post any kind of content, regardless of their particular talents, knowledge, credentials, biases or possible hidden agendas.
After reading various sources about Web 2.0, hypertext, hypermedia, interactivity and social media, I’ve learned that the two major paradigm shifts during this phase are user-generated content and cloud computing. If I were to choose which of the two manifests the concepts of Web 2.0 more, I would have to choose user-generated content, because first of all cloud computing would not exist if it weren’t for the data and information uploaded by the internet users. Second, because a lot of breakthroughs happened not only in human socializing per se but also in marketing and advertising.
For now I believe that the ultimate manifestation of Web 2.0 lies in social media.
Web 2.0; Wikipedia; http://en.wikipedia.org/wiki/Web_2.0
 Web 2.0; Investopedia Financial Dictionary; http://www.investopedia.com/terms/w/web-20.asp
 Hypertext; Wikipedia ; http://en.wikipedia.org/wiki/Hypertext
 Hypertext; Lincoln University Internet Encyclopedia; http://www.lincoln.edu/math/rmyrick/ComputerNetworks/InetReference/12.htm
 Taking the "Hype" Out of Hypermedia: A Teaching Tool; Darren Hughes; http://www.longpauses.com/hype.htm
 What is hypermedia?; Chapter 2 of Hypermedia and the Web by David Lowe and Wendy Hall; http://users.ecs.soton.ac.uk/lac/LoweNHall/extracts/Hypermedia.html
 Interactivity;Wikipedia; http://en.wikipedia.org/wiki/Interactivity
 Want to start a start up?; http://paulgraham.com/web20.html
 Social Media; Wikipedia; http://en.wikipedia.org/wiki/Social_media
 User Generated Content, Social Media ,and Advertising — An Overview; http://www.iab.net/ugcplatform