Introduction to PHP

PHP is an extremely popular scripting language used, primarily, by web designers to create websites. Scripting languages are languages which are processed by a computer on an as-needed basis, and the source code is fed through an interpreter which converts the necessary instructions into machine code and delivers the output. PHP is a server-side technology which is used to handle the database, file manipulation, and display aspects of the website. The source code is written by a programmer to manipulate all of the data in the background and finally feed the data to the user in a format that a web browser can understand and display.

The reason for PHP's popularity is that it is easy to work with and lends itself to programming on the web. Since it was recognized as being a highly-useful technology, several aspiring web developers learned PHP, furthering its propagation in the web. Another reason for its popularity is that it is an entirely free technology which can also be used on a variety of platforms, so the programmer doesn't need to relearn or convert the code when it needs to be transported to another platform. It's cross-platform and object-oriented nature also allowed it to easily be split up into “snippets”, or pieces of source code, which could act on their own and be distributed to other programmers for use in their own websites.

Another advantage to using PHP is that, since it is processed by an interpreter at the time that it is run, you can change the source code to immediately make a change to a website or application without recompiling it. One of the drawbacks of PHP is that there are several remotely-accessible exploits which will make the server vulnerable to attacks. Many of these exploits are documented, and patches are available to fix a great many of them, but the diligence of the system administrator and the programmer is the determining factor in whether or not a system will be secure behind a PHP program.

To learn more about PHP visit w3Schools PHP tutorial.