Assignment 1

Answers to Questions from Textbook

1 What is the task of a DNS server?

The task of a DNS server is to translate a human readable domain name or URL into a machine readable IP address.

2 In what common situation is a document returned by a Web server created after the request is recieved?

A document returned by a web server is created after the request is recieved when server-side scripting is necessary, such as a search query, form submission, and other similar user-specific interaction.

3 What is the relationship between Java and Javascript?

Java and Javascript are both OOP languages, but developed by different companies for different purposes. They have similar names and syntax, and Java may be implemented on a webpage using Javascript, but beyond that, they are very different. They are also both commonly used for internet applications.

4 Where is the Javascript code interpreted?

Javascript code is interpreted in the browser.

5 Where are CGI programs executed?

Common Gateway Interface programs are executed on the server side.

6 Describe the relationship between XML, SGML, HTML and XHTML

XML, SGML, HTML and XHTML are all markup languages, and are all inter-related. XML, or Extensible Markup Language, was originally a subset of SGML, Standard Generalized Markup Language. SGML was originally used to create shareable machine-readable documents that would be readable in decades to come. From that, XML was created as a markup language that could define any content, due to its expandability. HTML, HyperText Markup Language, is the language typically used for webpages to define structure and appearance of the content, as well as to create interactive content. HTML, like XML, was originally a subset of SGML. XHTML, Extensible HyperText Markup Language, is a subset of XML, not SGML, and has the same function as HTML, but the same restrictive syntax as XML, and therefore can use the same parser as XML.