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Introduction

The laboratory facility for the course is not set up yet, so we will use this first part of the course to develop some understanding of how the Internet and the World Wide Web works, and to practice looking at web sites from a developer’s perspective.

The Assignment

Read the first five articles in the Opera/Yahoo Web Standards Curriculum (don’t panic: each “article” is quite short), and answers the following questions:
  1. In what year did the Internet as we know it first become operational?

    “…in 1982 the ARPANET connections outside of the US were converted to use the new "TCP/IP" protocol. The Internet as we know it had arrived.”

  2. What is the relationship between the Internet and the World Wide Web?

    The World Wide Web Uses the Internet to exchange messages according to the HyperText Transfer Protocol.

  3. What code did Tim Berners-Lee first release to the public in 1993 while he was at CERN?

    The source code for the “WorldWideWeb”—programs that implemented message exchanges between computers using the HTTP protocol, plus the specifications for HTML for structuring hypertext documents to be exchanged using HTTP.

  4. What is the name of the organization that Tim Berners-Lee founded at MIT in 1994?

    The World Wide Web Consortium, known as the W3C.

  5. Chapter 3 says, “Every request/response starts by typing a Universal Resource Locator (URL) into the address bar of your web browser, …” But there is another way to make a URL request besides typing it. What is it?

    Click on a link.

  6. What are the three principle components of a URL, and how are they specified in a URL string?

    The protolol, the host address, and the path. The protocol is specified before the characters ://, as in http://. The host name is given immediately after the :// part, and ends with the next slash in the URL. The path is everything to the right of the host name. (Note: there may be a port number at the end of the host name, using a : to separate those two parts; there may be a query string following the path; a ? marks the start of a query.

  7. What does DNS stand for, and what role does it play in making Internet requests?

    The Domain Name Service translates fully qualified domain names (FQDNs), like babbage.cs.qc.cuny.edu into internet protocol (IP) addresses, like 149.4.211.122. The internet uses IP addresses for the actual routing of messages between computers, but it is easier for people to work with FQDNs.

  8. What is HTTP, and how does it relate to the World Wide Web?

    The HyperText Transfer Protocol is a set of rules for using the internet to send messages between web browsers and web servers. The World Wide Web is another name for using the internet to exchange messages using HTTP. Other internet protocols include SMTP for email and VOIP for telephone.

  9. Define the following HTML terms: element, start tag, end tag, attribute, attribute name, attribute value, and element content.

    An element is everything from the beginning of a start tag to the end of the corresponding end tag. The start tag consists of < followed by the name of the tag, followed by any number (possibly zero) of attributes, followed by >. The end tag starts with </, the tag name again, and >.The element content is everything from the > of the start tag to the < of the end tag; elements may be nested inside the contents of other elements. If an element has no content, the end tag may be combined with the start tag by putting a / just before its >. An attribute is a name-value pair: the name is made of letters and numbers, followed immediately by an equal sign, followed immediately by the attribute value, which must be inside quotation marks.

  10. What are the three components of a static web page, and what language is used for each?
    1. Content markup: HTML or XHTML
    2. Appearance: CSS
    3. Behavior: JavaScript
  11. Give the names of 4 different browsers.

    Firefox, Internet Explorer, Opera, Safari. (There are many others.)