PHP is a very powerful web-programming language which was designed to produce dynamic web pages. The main application of PHP lies in server-side scripting. However, PHP Scripts are often used to function as the back-end software for a website. They are often scripted by the use of a command line interface, which is also called as Code View interface.
PHP Scripts are very powerful and innovative - they have proven to introduce standardized ways of declaring constructors and destructors and various exception handling models to even object-oriented programming languages, of the likes of C++. A very popular PHP Script is PHPbb, a forum script. It is free and is comparable to the best available commercial forum script in the market. The Output Buffering characteristic/feature of PHP Scripts help in compressing a site's web pages, and that’s a good thing because this makes a lot of difference to your website's bandwidth.
PHP Power
PHP Scripts are used in millions of websites today, because of they're easily to install and use and they come with powerful and feature-rich applications. Net craft’s April 2006 PHP usage report says that over 20 million top-level domains on the internet use PHP Scripts, in one form or another.
Integration
PHP is a very accommodative language. It can well be integrated with HTML, with ease. When PHP scripts/mini-scripts are embedded in HTML, they often form a very powerful combination so as to even control the flow of a webpage.
When used in External JavaScript, PHP and JavaScript form a very strong combination, and have the potential of achieving limitless possibilities.
Developer Flexibility
As is often the case with various scripting languages/platforms, almost every PHP script is kept as a source code easily readable by humans and not just computers, even when deployed on production servers on the web. Many code optimizers are available in PHP Scripts, which tend to augment the quality of the final script by reduction in size. They further make changes, which result in the reduction of execution time and improvement in performance. PHP compilers always offer a lot of opportunities which help in easy optimization of the code. By the use of caching, accelerators in PHP (Scripts) offer significant gains in performance. This further helps to avoid the extra work on the server, as there is no need to parse and compile the code at every instant the script loads.
How secure is it?
While PHP and PHP Scripts are immensely popular and easily accessible by fairly new webmasters because of the pre-built utility scripts and various auto-installers, it doesn't come as a surprise that applications and scripts built on PHP are a big target of hackers. One big minus point, but many argue that open-source and free availability is the reason why PHP is prone to hack attacks, as such crimes will most often not be dealt with, very seriously.
