PHP is essentially a general-purpose scripting language. It is particularly suitable for server-side web development. PHP usually runs on a web server. Every PHP codebase in any requested file can be executed by the PHP runtime. This supports creation of dynamic web page content. The other utilities of it place in command-line scripting and client-side GUI applications. PHP is portable on most of the web servers, various operating systems and platforms. It can also be utilized with several relational database management systems. PHP team supplies the complete source code for PHP users to develop, modify and expand for their own utilization. So it is offered free of cost.
PHP mostly operates as a sift. It takes input from a file or stream which encloses text and/or PHP instructions and yields output of another stream of data. The most frequent output is HTML. Since the arrival of PHP 4, the PHP parser compiles input to give bytecode output for processing by the Zend Engine. It consequences in an enhanced performance over its interpreter predecessor.
PHP was initially developed to create dynamic web pages. It now targets mainly on server-side scripting. It acts quite alike to other server-side scripting languages that provide dynamic content from a web server to a client. Some of its market challengers are Sun Microsystems' JavaServer Pages, Microsoft's Active Server Pages and mod perl.
It has also alert on the development of numerous frameworks that give building blocks and a design structure to support rapid application development (RAD). Some of these are CakePHP, CodeIgniter, Symfony and Zend Framework. All of them propose features similar to other web application frameworks.
PHP is the P in the package called LAMP architecture in web industry alongside Linux, Apache and MySQL. The group is a way of deploying web applications. P may also pass on to Perl or Python or some combination of the three.