Web 2.0

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Web 2.0 refers to World Wide Web websites that emphasize user-generated content, usability (ease of use, even by non-experts), and interoperability (this means that a website can work well with other products, systems, and devices) for end users. The term was invented by Darcy DiNucci in 1999 and popularized several years later by Tim O’Reilly and Dale Dougherty at the O’Reilly Media Web 2.0 Conference in late 2004. Web 2.0 does not refer to an update to any technical specification, but to changes in the way Web pages are designed and used.

A Web 2.0 website may allow users to interact and collaborate with each other in a social media dialogue as creators of user-generated content in a virtual community, in contrast to the first generation of Web 1.0-era websites where people were limited to the passive viewing of content. Examples of Web 2.0 features include social networking sites and social media sites (e.g., Facebook), blogs, wikis, folksonomies (“tagging” keywords on websites and links), video sharing sites (e.g., YouTube), hosted services, Web applications (“apps”), collaborative consumption platforms, and mashup applications.

Whether Web 2.0 is substantively different from prior Web technologies has been challenged by World Wide Web inventor Tim Berners-Lee, who describes the term as jargon. His original vision of the Web was “a collaborative medium, a place where we could all meet and read and write.” On the other hand, the term Semantic Web (sometimes referred to as Web 3.0) was coined by Berners-Lee to refer to a web of content where the meaning can be processed by machines.

Web 1.0

Web 1.0 is a retronym referring to the first stage of the World Wide Web’s evolution. According to Cormode, G. and, Krishnamurthy, B. (2008): “content creators were few in Web 1.0 with the vast majority of users simply acting as consumers of content.” Personal web pages were common, consisting mainly of static pages hosted on ISP-run web servers, or on free web hosting services such as GeoCities. With the advent of Web 2.0, it was more common for the average web user to have social networking profiles on sites such as Myspace and Facebook, as well as personal blogs on one of the new low-cost web hosting services or a dedicated blog host like Blogger or LiveJournal. The content for both was generated dynamically from stored content, allowing for readers to comment directly on pages in a way that was not previously common.

Some Web 2.0 capabilities were present in the days of Web 1.0, but they were implemented differently. For example, a Web 1.0 site may have had a guestbook page to publish visitor comments, instead of a comment section at the end of each page. Server performance and bandwidth considerations had to be taken into account, and a long comments thread on each page could potentially slow down the site. Terry Flew, in his 3rd edition of New Media, described the differences between Web 1.0 and Web 2.0:

“move from personal websites to blogs and blog site aggregation, from publishing to participation, from web content as the outcome of large up-front investment to an ongoing and interactive process, and from content management systems to links based on “tagging” website content using keywords (folksonomy)”.

Flew believed it to be the above factors that form the basic change in trends that resulted in the onset of the Web 2.0 “craze”.

Characteristics

Some design elements of a Web 1.0 site include:

Static pages instead of dynamic HTML.
Content served from the server’s filesystem instead of a relational database management system (RDBMS).
Pages built using Server Side Includes or Common Gateway Interface (CGI) instead of a web application written in a dynamic programming language such as Perl, PHP, Python or Ruby.
The use of HTML 3.2-era elements such as frames and tables to position and align elements on a page. These were often used in combination with spacer GIFs.
Proprietary HTML extensions, such as the <blink> and <marquee> tags, introduced during the first browser war.
Online guestbooks.
GIF buttons, graphics (typically 88×31 pixels in size) promoting web browsers, operating systems, text editors and various other products.
HTML forms sent via email. Support for server side scripting was rare on shared servers during this period. To provide a feedback mechanism for web site visitors, mailto forms were used. A user would fill in a form, and upon clicking the form’s submit button, their email client would launch and attempt to send an email containing the form’s details. The popularity and complications of the mailto protocol led browser developers to incorporate email clients into their browsers.

Web 2.0

The term “Web 2.0” was first used in January 1999 by Darcy DiNucci, an information architecture consultant. In her article, “Fragmented Future”, DiNucci writes:

The Web we know now, which loads into a browser window in essentially static screenfuls, is only an embryo of the Web to come. The first glimmerings of Web 2.0 are beginning to appear, and we are just starting to see how that embryo might develop. The Web will be understood not as screenfuls of text and graphics but as a transport mechanism, the ether through which interactivity happens. It will appear on your computer screen, on your TV set your car dashboard your cell phone hand-held game machines maybe even your microwave oven.

The key features of Web 2.0 include:

Folksonomy – free classification of information; allows users to collectively classify and find information (e.g. “tagging” of websites, images, videos or links)
Rich user experience – dynamic content that is responsive to user input (e.g., a user can “click” on an image to enlarge it or find out more information)
User participation – information flows two ways between site owner and site users by means of evaluation, review, and online commenting. Site users also typically create user-generated content for others to see (e.g., Wikipedia, an online encyclopedia that anyone can write articles for or edit)
Software as a service (SaaS) – Web 2.0 sites developed APIs to allow automated usage, such as by a Web “app” (software application) or a mashup
Mass participation – near-universal web access leads to differentiation of concerns, from the traditional Internet user base (who tended to be hackers and computer hobbyists) to a wider variety of users

Technologies

The client-side (Web browser) technologies used in Web 2.0 development include Ajax and JavaScript frameworks. Ajax programming uses JavaScript and the Document Object Model to update selected regions of the page area without undergoing a full page reload. To allow users to continue to interact with the page, communications such as data requests going to the server are separated from data coming back to the page (asynchronously). Otherwise, the user would have to routinely wait for the data to come back before they can do anything else on that page, just as a user has to wait for a page to complete the reload. This also increases overall performance of the site, as the sending of requests can complete quicker independent of blocking and queueing required to send data back to the client. The data fetched by an Ajax request is typically formatted in XML or JSON (JavaScript Object Notation) format, two widely used structured data formats. Since both of these formats are natively understood by JavaScript, a programmer can easily use them to transmit structured data in their Web application. When this data is received via Ajax, the JavaScript program then uses the Document Object Model (DOM) to dynamically update the Web page based on the new data, allowing for a rapid and interactive user experience. In short, using these techniques, Web designers can make their pages function like desktop applications. For example, Google Docs uses this technique to create a Web-based word processor.

As a widely available plugin independent of W3C standards (the World Wide Web Consortium is the governing body of Web standards and protocols), Adobe Flash is capable of doing many things that were not possible pre-HTML5. Of Flash’s many capabilities, the most commonly used is its ability to integrate streaming multimedia into HTML pages. With the introduction of HTML5 in 2010 and growing concerns with Flash’s security, the role of Flash is decreasing. In addition to Flash and Ajax, JavaScript/Ajax frameworks have recently become a very popular means of creating Web 2.0 sites. At their core, these frameworks use the same technology as JavaScript, Ajax, and the DOM. However, frameworks smooth over inconsistencies between Web browsers and extend the functionality available to developers. Many of them also come with customizable, prefabricated ‘widgets’ that accomplish such common tasks as picking a date from a calendar, displaying a data chart, or making a tabbed panel. On the server-side, Web 2.0 uses many of the same technologies as Web 1.0. Languages such as Perl, PHP, Python, Ruby, as well as Enterprise Java (J2EE) and Microsoft.NET Framework, are used by developers to output data dynamically using information from files and databases. This allows websites and web services to share machine readable formats such as XML (Atom, RSS, etc.) and JSON. When data is available in one of these formats, another website can use it to integrate a portion of that site’s functionality.

Concepts

Web 2.0 can be described in three parts:

Rich Internet application (RIA) — defines the experience brought from desktop to browser, whether it is “rich” from a graphical point of view or a usability/interactivity or features point of view.
Web-oriented architecture (WOA) — defines how Web 2.0 applications expose their functionality so that other applications can leverage and integrate the functionality providing a set of much richer applications. Examples are feeds, RSS feeds, web services, mashups.
Social Web — defines how Web 2.0 websites tend to interact much more with the end user and make the end user an integral part of the website, either by adding his or her profile, adding comments on content, uploading new content, or adding user-generated content (e.g., personal digital photos).

As such, Web 2.0 draws together the capabilities of client- and server-side software, content syndication and the use of network protocols. Standards-oriented Web browsers may use plug-ins and software extensions to handle the content and the user interactions. Web 2.0 sites provide users with information storage, creation, and dissemination capabilities that were not possible in the environment now known as “Web 1.0”.

Web 2.0 sites include the following features and techniques, referred to as the acronym SLATES by Andrew McAfee:

Search – Finding information through keyword search.
Links to other websites – Connects information sources together using the model of the Web.
Authoring – The ability to create and update content leads to the collaborative work of many authors. Wiki users may extend, undo, redo and edit each other’s work. Comment systems allow readers to contribute their viewpoints.
Tags – Categorization of content by users adding “tags” — short, usually one-word or two word descriptions — to facilitate searching. For example, a user can tag a metal song as “death metal”. Collections of tags created by many users within a single system may be referred to as “folksonomies” (i.e., folk taxonomies).
Extensions – Software that makes the Web an application platform as well as a document server. Examples include Adobe Reader, Adobe Flash, Microsoft Silverlight, ActiveX, Oracle Java, QuickTime, and Windows Media.
Signals – The use of syndication technology, such as RSS feeds to notify users of content changes.

While SLATES forms the basic framework of Enterprise 2.0, it does not contradict all of the higher level Web 2.0 design patterns and business models. It includes discussions of self-service IT, the long tail of enterprise IT demand, and many other consequences of the Web 2.0 era in enterprise uses.

Usage

A third important part of Web 2.0 is the social web. The social Web consists of a number of online tools and platforms where people share their perspectives, opinions, thoughts and experiences. Web 2.0 applications tend to interact much more with the end user. As such, the end user is not only a user of the application but also a participant by: