1. Introduction to World Wide Web
Imran Rashid
CTO at ManiWeber Technologies

2. Outline World Wide Web History How Web Works
What is URL, DNS, Protocol, Browser & HTML
What is DTD, CSS, XML & RSS
What is JavaScript, AJAX, PHP & SQL

3. World Wide Web History

4. World Wide Web History
Information medium accessible via devices using internet
Not a synonym for the internet itself, but the web is a service that operates over the internet
Tim Berners-Lee invented the world wide web in 1989, about 20 years after the first connection was established over what is today known as the internet
Tim was a software engineer at CERN, the large particle physics laboratory near Geneva, Switzerland
Proposal specified a set of technologies that would make the internet truly accessible & useful to people [1989]

5. World Wide Web History
Specified the three fundamental technologies HTML, URI & HTTP [1990]
Tim also wrote the first web page editor/browser (WorldWideWeb) & the first Web server (httpd) [1991]
CERN announced that the www technology would be available for anyone to use on a royalty-free basis [1993]
Tim founded the world wide web consortium (W3C) to develop or gather web standards [1994]

6. How Web Works

7. How Web Works
The client and server are basically two parts of a distributed computing model
Client/server is a program relationship in which one program (the client) requests a service or resource from another program (the server)
In this model, a user uses a client computer which sends requests to the server
The server then processes the request and creates the appropriate response which it sends back to the client
The client is usually the initiator

8. How Web Works

9. How Web Works

10. What is URL, DNS, Protocol, Browser & HTML

11. What is URL, DNS, Protocol, Browser & HTML
Uniform resource locator (URL) anatomy

12. What is URL, DNS, Protocol, Browser & HTML
Sub-domains
WWW is default sub-domain for any web server
Home page is always index or default with extentions
You can create multiple sub-domains

13. What is URL, DNS, Protocol, Browser & HTML
Domain name system (DNS)
System used to translate word-based addresses of systems (e.g. to the numerical IP (e.g ) address

14. What is URL, DNS, Protocol, Browser & HTML
Hypertext transfer protocol (HTTP)
Protocols allow devices to talk to each other…
HTTP is stateless?

15. What is URL, DNS, Protocol, Browser & HTML
Web browser
A browser is a software application used to locate, retrieve and display content on the world wide web, including web pages, images, video and other files

16. What is URL, DNS, Protocol, Browser & HTML
Hypertext Markup Language (HTML)
That may sound scary, but it simply means it is a language for describing web-pages using ordinary text

17. What is DTD, CSS, XML & RSS

18. What is DTD, CSS, XML & RSS Document type definition (DTD)
Defines the structure and the legal elements and attributes of an HTML/XHTML/XML document
A DTD can be declared inside an XML document or in an external file

19. What is DTD, CSS, XML & RSS

20. What is DTD, CSS, XML & RSS Cascading Style Sheets (CSS)
A style-sheet language developed to control the presentation of HTML documents

21. What is DTD, CSS, XML & RSS

22. What is DTD, CSS, XML & RSS

23. What is DTD, CSS, XML & RSS Extensible markup language (XML)
A semantic markup language containing rules for defining document structure and data

24. What is DTD, CSS, XML & RSS Really simple syndication (RSS)
RSS feeds use standardized tags for describing feeds
Structure included headlines, descriptions, links and more
Feed creation & reading is typically a server-side process

25. What is JavaScript, AJAX, PHP & SQL

26. What is JavaScript, AJAX, PHP & SQL
A scripting language used to add interactivity and functionality to websites (it has nothing to do with Java!)

27. What is JavaScript, AJAX, PHP & SQL
Asynchronous JavaScript & XML (AJAX)
The method of exchanging data with a server, & updating parts of a web page - without reloading the entire page

28. What is JavaScript, AJAX, PHP & SQL
PHP: Hypertext Preprocessor (PHP)
A widely-used open source general-purpose scripting language that is especially suited for web development and can be embedded into HTML

29. What is JavaScript, AJAX, PHP & SQL
Structured query language (SQL)
Standard query language for managing & retrieving information from databases

30. Any ?