PHP

PHP is an interpreted programming language, originally designed to create dynamic web pages. Its main use is server-side scripting, but today it can also be used on a command line or alogn with graphic interface software using libraries such as Qt or GTK+. It can be deployed on most web servers and operating systems without cost. PHP is already installed in more than 20 million websites and a million servers. Since august 2005, PHP has shared this preponderant place with other new but not so powerful languages. Sites that trust this language go from Wikipedia to Facebook. It is also the most popular Apache module. The latest version released is the 5.3.4 on December 10, 2010.

Highlights:

• It's a multi platform language. Completeley oriented to the development of dynamic web applications with access to a database.
• The source code is invisible to the browser and to the client since the server executes the code and sends an HTML result to the browser. This makes PHP safe and trusted.
• It can be connected to most databases used nowadays. Specially with MySQL and PostgreSQL.
• It can be widely expanded using all the available modules called extensions.
• There is a lot of documentation at its official website. All functions are explained with examples within a single help file
• It's free, which makes it a great choice for everyone
• Supports object oriented programming
• A wide native library of useful functions.
• Does not require variable type definition even though its variables can be evaluated by the value they are carrying at execution time.
• Supports exception handling (begins with PHP5).
• Even though PHP does not force the programmer to follow a determined methodology, it is still oriented to be used with one. The developer can apply any technique he wants keeping an organized environment with a structured and manageable code. An example of this is MVC oriented development using PHP

Taken from Wikipedia, February 2010