Web 2.0

Web 2.0 describes World Wide Web sites that emphasize user-generated content, usability, and interoperability. The term was popularized by Tim O'Reilly and Dale Dougherty at the O'Reilly Media Web 2.0 Conference in late 2004, though it was coined by Darcy DiNucci in 1999. Although Web 2.0 suggests a new version of the World Wide Web, it does not refer to an update to any technical specification, but rather to cumulative changes in the way Web pages are made and used.

A Web 2.0 site 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 Web sites where people are limited to the passive viewing of content. Examples of Web 2.0 include social networking sites, blogs, wikis, folksonomies, video sharing sites, hosted services, Web applications, and mashups.

Whether Web 2.0 is substantively different from prior Web technologies has been challenged by World Wide Web inventor Sir 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 Tim Berners-Lee for a web of data that can be processed by machines.

.web

.web is a generic top-level domain that will be awarded by ICANN to one of seven registry applicants. The .web TLD will be in the official root once ICANN awards the registry contract.

Historic information about .web

.web was operated as a prospective registry, not in the official root, by Image Online Design since 1995. It originated when Jon Postel, then running the top level of the Domain Name System basically single-handedly, proposed the addition of new top-level domains to be run by different registries. Since Internet tradition at the time emphasized "rough consensus and running code", Christopher Ambler, who ran Image Online Design, saw this as meaning that his company could get a new TLD into the root by starting up a functional registry for it. After asking and receiving permission from IANA to do so, IOD launched .web, a new unrestricted top level domain.

Since then IOD has tried to get their domain into the official root through several plans to admit new top-level domains. Several new-TLD plans in the late 1990s, including Postel's original proposal, failed to reach sufficient consensus among the increasingly contentious factions of the Internet to admit any new TLDs, including .web. When ICANN accepted applications for new TLDs in 2000 which resulted in the seven new domains added soon afterward, IOD's application was not approved; neither was it officially rejected, however, since all unapproved applications remain in play for possible future acceptance. A second round of new TLDs, however, was done entirely with new applications, and only for sponsored domains (generally intended for use by limited communities and run by nonprofit entities). The .web registry remains hopeful, however, that their application will eventually be approved. On May 10, 2007, ICANN announced the opening of public comments towards a new, third round of new gTLDs, a round in which IOD has not participated.

Web

Web or Webs may refer to:

Arachnology

Computing

Mathematics

Web (differential geometry)

In mathematics, a web permits an intrinsic characterization in terms of Riemannian geometry of the additive separation of variables in the Hamilton–Jacobi equation.

Formal definition

An orthogonal web on a Riemannian manifold (M,g) is a set of n pairwise transversal and orthogonal foliations of connected submanifolds of codimension 1 and where n denotes the dimension of M.

Note that two submanifolds of codimension 1 are orthogonal if their normal vectors are orthogonal and in a nondefinite metric orthogonality does not imply transversality.

Alternative definition

Given a smooth manifold of dimension n, an orthogonal web (also called orthogonal grid or Ricci’s grid) on a Riemannian manifold (M,g) is a set of n pairwise transversal and orthogonal foliations of connected submanifolds of dimension 1.

Remark

Since vector fields can be visualized as stream-lines of a stationary flow or as Faraday’s lines of force, a non-vanishing vector field in space generates a space-filling system of lines through each point, known to mathematicians as a congruence (i.e., a local foliation). Ricci’s vision filled Riemann’s n-dimensional manifold with n congruences orthogonal to each other, i.e., a local orthogonal grid.