php

why learn php 

Introduction to php

PHP is server side scripting language implemented by rasmus lerdorf in 1994 using  C and  perl softwares.

Using  PHP, we can develop  dynamic web pages.

Rasmus lerdary implemented PHP 1.0 too track total no of visitors in his server.

PHP  stands for personal home page . It also has alias  name hypertext preprocessor.

Features of PHP

PHP is cross platform  i.e. it support any type of operating system .   example  window , Linux etc.

PHP is  cross database  i.e.,  it supports any type of database server  example :-  MYSql, SQL server , etc.

It  is providing built in libraries to connect  with MYSQL data base .

PHP is croos web server, it server, it supports IIS , apache , Tomcat. Etc.

PHP is open source software.

PHP is   very simple to develop logic.

Execution of  PHP   is very  fast  example  facebook, because of  zend  engine .

PHP 5.0  is supporting no of object  oriented programming concepts.

PHP supports different types  of  content management . system software, Joomla,    drupal,  wordpress,  etc .

These software provides pre-implemented  logic to develop websites or web applications.

Zend organization  is maintaining PHP , they  introduces no of  tools  and  editors  to work with PHP.

PHP support different types of editors  to develop program or  application. We  can also use light weight editors  example  Notepad, edit+ , notepad++  etc.

PHP supports different types of security functionalities to apply  security to application.

Example :-  one way , encryption, two-way encryption, authentication etc.

Client  Server  Architecture:

 Web server

Web server is a software used to run web applications , Main function of sends is to handle  request from client and  sends response to client.

Example :- IIS , Apache, Tomcat , etc.

Web Browser

It is a software  used to open web pages from server.

example :-  firfox, chrome , etc.

Client-side Script

If any script executes in client  system with  the help  of browser,  comes under client-side script ., example :- HTML, JavaScript, etc.

Server-side Script:

  1. If any script executes with web  server , it comes under server-side script.
  2. This  script runs in server and output is loading into browser. Example – PHP, ASP, etc.
  PHP 

PHP is loosely typed language so that  there is no need to provide data types at the time of variable declarations.

Variables names in PHP should start with “$”  symbol.

PHP is  case sensitive in variables point of view and case  insensitive in functions point of view.

Every statement in PHP should be terminated with  ‘;’.

PHP file extension should be  PHP.

PHP script , we should place with in the script declaration style tags.

<?php

—-

—-

?>

No of open source software’s are  available to install , PHP , Mysql and apache ,

they are  :..

Lamp

  1. Stands for Linux apache  Mysql PHP .
  2. Supports only Linux  , OS, and downloads apache, MySql and PHP softwares.

WAMP

  1. Stands for windows , Apache , Mysql , PHP .
  2. Supports only windows OS.

XAMPP

  1. Stands  for vross OS  , Apache , Mysql, PHP and perl
  2. Support all OS.
  3. Xampp is available with different versions  1.x,2.x,;;;;;etx.

XAMPP Control Panel 

By using Xampp control panel, we can start apache MySql, data base servers after installation of xampp, xampp control panel short out icon will appear on screen(desktop).

Folder structure of XAMPP

After installation of Xampp software  we can find  out xampp folder in directory location. It contains no of  subfolder and configuration settings.

Htdocs

It is root directory of apache server . all PHP program should  be saved at this location only.

Php.int

php initialsation is a configuration setting file of php available in

Httpd.conf

It is apache server  configuration setting  file available  in xampp/apache/conf folder.

Tmp 

Temporary memory location of apache server. Uploaded files and configuration setting of session are available at this location.

Php my admin  

it ia an IDE to work with  Mysql data base .It is available with xampp installation.