Showing posts with label Web Development. Show all posts
Showing posts with label Web Development. Show all posts

Hyper Text Transfer Protocol - HTTP

HTTP stands for Hypertext Transfer Protocol. It is an TCP/IP based communication protocol which is used to deliver virtually all files and other data, collectively called resources, on the World Wide Web. These resources could be HTML files, image files, query results, or anything else. 
An HTTP conversation

HTTP is the set of rules governing the format and content of the conversation between a Web client and server.

HTTP Message
•  HTTP uses the client-server model: An HTTP client opens a connection and sends a request message to an HTTP server; the server then returns a response message, usually containing the resource that was requested. After delivering the response, the server closes the connection.

HTTP transaction

      HTTP Message
    The format of the request and response messages are similar and will have following structure
    - An initial line
    - Zero or more header lines
    - A blank line
    - An optional message body like file, query data or query output. 
HTTP Methods
  •      GET
  •      POST
  •      HEAD
HTTP Request Types
•GET (default) and POST do basically the same thing: Send data from the client to the server. 
However, they have some differences:
–Appends form data directly to the end of the UR— visible to users 
(not suitable for sending passwords)
–Limited to 2,048 characters for the entire URL
–Result page can be bookmarked and cached

–Sends form data in the HTTP request—invisible to users
–Virtually no limit (but check your specific configuration) 
–Results are not cacheable or bookmarkable

The HEAD Method
 A HEAD request is just like a GET request, except it asks the server to return the response headers only, and not the actual resource (i.e. no message body). This is useful to check characteristics of a resource without actually downloading it, thus saving bandwidth. Use HEAD when you don't actually need a file's contents.
     The response to a HEAD request must never contain a message body, just the status line and headers.

HTTP Header Fields
HTTP Status Codes

Example of an HTTP Request from a Web browser

HTTP version 1.1 specifies a persistent connection by default.

  scenario in which an electronic store can benefit from the use of cookies. Assume a shopper wants to buy a toy from an electronic store named BestToys. The shopper browser (client) sends a request to the BestToys server. 

Introduction to Web Technologies


2.Clients softwares
4.Client side technologies
5.Server side technologies
6.Database Servers

Find download link of this presentation from the bottom of this post. 

 Click to download this ppt .

Cascading Style Sheet -CSS


                                    1   Introduction
                             2   Inline Styles
                             3   Embedded Style Sheets
                             4   Conflicting Styles
                             5   Linking External Style Sheets
                             6   W3C CSS Validation Service
                             7   Positioning Elements
                             8   Backgrounds
                             9   Element Dimensions
                             10 Text Flow and the Box Model
                             11 User Style Sheets
                             12 Web Resources

Find download link of this presentation from the bottom of this post.

 Click to download this ppt .