[Web Research ]
1. The World Wide Web Consortium creates standard for the Web. Visit its site athtt p://www.w3c.org and then answer the following questions:
a. How did the W3C get started?
In 1998,Tim Berners-Lee invented the World Wide Web…
He coined the term "World Wide Web," wrote the first World Wide Web server, "httpd," and the first client program (a browser and editor), "Worldwide Web," in October 1990. He wrote the first version of the "Hypertext Markup Language" (HTML), the document formatting language with the capability for hypertext links that became the primary publishing format for the Web. His initial specifications for URIs, HTTP, and HTML were refined and discussed in larger circles as Web technology spread
In October 1994, Tim Berners-Lee founded the World Wide Web Consortium (W3C) at the Massachusetts Institute of Technology, Laboratory for Computer Science [MIT/LCS] in collaboration with CERN, where the Web originated, with support from DARPA and the European Commission. For further information on the joint initiative and the contributions of CERN, INRIA, and MIT.
In October 1994, Tim Berners-Lee founded the World Wide Web Consortium (W3C) at the Massachusetts Institute of Technology, Laboratory for Computer Science [MIT/LCS] in collaboration with CERN, where the Web originated with support from DARPA and the European Commission. For further information on the joint initiative and the contributions of CERN, INRIA, and MIT.
b. Who can join the W3C? What dose it cost to join?
Membership in W3C is open to all types of organizations (including commercial, educational and governmental entities) and individuals. Any entity that can sign the Membership Agreement can become a Member. Members may be either for-profit or not-for-profit organizations. Most Members invest significant resources into Web technologies. They may be developing Web-based products, using Web technologies as an enabling medium, conducting research on the Web, or developing specifications based on W3C work.
Costs vary depending on the city, which belongs to the Organization .
c. The W3C home page lists a number of technologies. Choose one that interest you, click its link, and read the
associated pages. List three facts or issues you discover (other than issues discussed in class).
Hypertext Transfer Protocol (HTTP)
1. Hypertext Transfer Protocol (HTTP) is an application-level protocol for distributed, collaborative, hypermedia information systems. Its use for retrieving inter-linked resources led to the establishment of the World Wide Web.
2. HTTP is a request/response standard of a client and a server. A client is the end-user, the server is the web site. The client making a HTTP request—using a web browser, spider, or other end-user tool—is referred to as the user agent. The responding server—which stores or creates resources such as HTML files and images—is called the origin server. In between the user agent and origin server may be several intermediaries, such as proxies, gateways, and tunnels.
3. Typically, an HTTP client initiates a request. It establishes a Transmission Control Protocol (TCP) connection to a particular port on a host (port 80 by default; see List of TCP and UDP port numbers). An HTTP server listening on that port waits for the client to send a request message. Upon receiving the request, the server sends back a status line, such as "HTTP/1.1 200 OK", and a message of its own, the body of which is perhaps the requested resource, an error message, or some other information.
4. HTTP defines eight methods (sometimes referred to as "verbs") indicating the desired action to be performed on the identified resource. What this resource represents, whether pre-existing data or data that is generated dynamically, depends on the implementation of the server. Often, the resource corresponds to a file or the output of an executable residing on the server.
HEAD
Asks for the response identical to the one that would correspond to a GET request, but without the response body. This is useful for retrieving meta-information written in response headers, without having to transport the entire content.
GET
Requests a representation of the specified resource. Note that GET should not be used for operations that cause side-effects, such as using it for taking actions in web applications. One reason for this is that GET may be used arbitrarily by robots or crawlers, which should not need to consider the side effects that a request should cause. See safe methods below.
POST
Submits data to be processed (e.g., from an HTML form) to the identified resource. The data is included in the body of the request. This may result in the creation of a new resource or the updates of existing resources or both.
HEAD
Asks for the response identical to the one that would correspond to a GET request, but without the response body. This is useful for retrieving meta-information written in response headers, without having to transport the entire content.
GET
Requests a representation of the specified resource. Note that GET should not be used for operations that cause side-effects, such as using it for taking actions in web applications. One reason for this is that GET may be used arbitrarily by robots or crawlers, which should not need to consider the side effects that a request should cause. See safe methods below.
POST
Submits data to be processed (e.g., from an HTML form) to the identified resource. The data is included in the body of the request. This may result in the creation of a new resource or the updates of existing resources or both.
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