PHP is a scripting language designed for developing dynamic web pages. While its principal purpose was server-side scripting, it has grown to incorporate a command line interface capability and can be used to develop client-side Graphical User Interface (GUI) applications as well.
PHP Syntax
A PHP file can also contain tags such as HTML and client side scripts such as JavaScript.
HTML is an added advantage when learning PHP Language. You can even learn PHP without knowing HTML but it’s recommended you at least know the basics of HTML.
Different Applications of PHP
Web Pages and Web-Based Applications:
Any web page or web application developed in the current ecosystem needs to offer a high degree of customization, provide highly interactive user interface, be capable of performing online transactions and integrate with database systems. Through its three-tiered architecture which works on browser, server and database system in a linear manner, PHP offers a reliable solution to achieve these features. As a consequence, PHP is used by over 82% of websites for server side programming; over 244 million websites are built using PHP. Further, web-based enterprise applications and a multitude of Facebook apps are also scripted in PHP.
Web Content Management Systems:
PHP offers support to numerous databases including MySQL, Oracle and MS Access and is capable of interacting with other services using protocols such as IMAP, LDAP, POP3, NNTP, SNMP, HTTP and COM . As a result, PHP has been used for creating popular web Content Management Systems (CMS), including WordPress and its plugins, user-facing portion of Facebook, Joomla, Drupal, Moodle, Silverstripe, MediaWiki, Digg and others.
eCommerce Applications:
From small businesses to large enterprises, selling to online shoppers is now an indispensable requirement. Through use of frameworks like CodeIgniter and CakePHP, PHP allows creation of eCommerce applications in a swift and simple manner. Many of the highly used eCommerce platforms, such as OpenCart, Magento, PrestaShop, Zen Cart, AgoraCart and Ubercart, have all been created on PHP.
Database management systems DBMS for database powered applications.
For more advanced topics such as interactive applications and web services, you will need JavaScript and XML.
I hope this information will be helpful!
Mark Wilson