INTRODUCTION ON PHP

We develop 3 types of applications –

• ·        Standalone Application
• ·        Mobile Applications
• ·        Web Applications

Every webpage is a combination of –

• ·        Designing – UI – Client side scripts – HTML, CSS etc
• ·        Coding – Logics – Server side scripting – PHP, JSP, ASP etc

Types of webpages –

• ·        Static – does not contain logics
• ·        Dynamic – Contains logic

Introduction to PHP

PHP is a server side scripting language implemented by Rasmus Lerdorf in 1994 using C and Perl software. Using PHP, we can develop dynamic webpages. Rasmus Lerdorf implemented PHP 1.0 to track total number of visitors in his server. PHP stands for Personal Home Page. It also has alias name Hypertext Preprocessor. PHP is loosely typed language so that there is no need to provide datatypes at the time of variable declaration. Variable name in PHP should start with $ symbol. PHP is case sensitive in variable 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 within the script declaration style tags -
<?php
--------
--------
?>

Features of PHP

• PHP is cross platform i.e. it supports any kind of operating system. Example – Windows, Linux etc.
• PHP is cross database i.e., it supports any kind of database server. Example – MySQL, SQL Server etc. It provides built-in libraries to connect with MySQL database.
• PHP is cross web server, it supports IIS, Apache, Tomcat etc.
• PHP is open source software.
• PHP is very simple to develop logics.
• Execution of PHP is very fast. Example – Facebook because of Zend engine.
• PHP 5.0 supports number of object oriented programming concepts.
• PHP supports different types of Content Management System softwares. Joomla, Drupal, Wordpress etc. These softwares provides pre-implemented logics to develop websites or web applications.
• Zend organization is maintaining PHP, they introduced number of tools and editors to work with PHP.
• PHP supports different types of editors to develop programs or applications. We can also use light weight editors like Notepad, Edit Plus etc.
• PHP supports different types of security functionalities to apply security to applications. Example – one-way encryption, two-way encryption, authentication etc.