1. Introduction to the World Wide Web & Internet CIS 101

2. WWW & Internet 1960s – ARPANET conceived as communication infrastructure for researchers to share access to supercomputers 1970s – Universities & research organizations around the world used ARPANET

3. WWW & Internet 1971 – File Transfer Protocol (FTP) allows users to copy from & to FTP server machines 1980 – TCP/IP was formalized 1991 – First Web browser & server 1993 – 50 servers on the Web 1993 – Web accounted for 1% of traffic 1990s – Web accounted for 75% of traffic

4. WWW & Internet Web browsers, which provided a simple graphical user interface, had increased usage FTP was a more complex line-command interface

5. WWW & Internet 3 Components of the Web 1. Uniform Resource Identifier (URI) 2. HTML (HyperText Markup Language) 3. HTTP (HyperText Transport Protocol)

6. WWW & Internet 1. Uniform Resource Identifier (URI) Denotes location of a resource 3 Parts a)Protocol for communicating with server (http:) b)Name of server (e.g. www.cnn.com) www.cnn.com c)Name of resource (e.g. picture1.gif) URLs are the most common URIs

7. WWW & Internet 2. HTML (HyperText Markup Language) Allows authors to format text, reference images and embed links to other documents

8. WWW & Internet HTML is a language used to design Web pages for the Internet HTML documents are displayed by means of a Web browser The browser interprets HTML and renders it

9. WWW & Internet HTML has gone through several versions, each of which expands the capabilities of HTML The most recent version of HTML is HTML 4.01

10. WWW & Internet Dynamic HTML (DHTML) is a term that describes a combination of HTML tags, cascading style sheets (CSS), and a scripting language such as JavaScript. DHTML allows users to create interactive, animated Web pages

11. WWW & Internet Extensible Markup Language (XML) is a markup language that uses tags to describe the structure and content of a document, not the format Extensible Hypertext Markup Language (XHTML) is a reformulation of HTML so it conforms to Extensible Markup Language (XML) rules

12. WWW & Internet Some HTML Editors Microsoft Word Microsoft FrontPage Internet Explorer Netscape Navigator

13. WWW & Internet HTML Tags Tags are instructions that HTML uses to tell the Web browser how to display text, images and other media Tags are enclosed in brackets Most tags have a start tag and an end tag

14. WWW & Internet HTML versus JavaScript HTML is static JavaScript allows Web pages to be dynamic JavaScript is a language that was developed strictly for use on the Web JavaScript can handle calculations, controls and validate forms with minimal programming effort

15. WWW & Internet JavaScript It is interactive, i.e. responds to the user Like HTML it uses open and close tags

16. WWW & Internet 3. HTTP (HyperText Transport Protocol) Allows Web components to communicate e.g. Client & Server Used to transfer HTML documents of the World Wide Web

17. Web Development

18. WWW & Internet What is the Internet? The international computer network of networks that connect government, academic and business institutions. What is the World Wide Web? A network of servers (computers that handle requests for data) linked together by a common protocol (set of rules/standards), allowing access to millions of hypertext resources (linked documents).