What is PHP?

Creating web pages using only XHTML and CSS places a big limit on how much a web site can do - basically, a web page coded this way is static, meaning that it will be displayed the same way every time it is loaded and doesn't change dynamically in any meaningful way while a user is viewing it.

These days most web sites need to do more than just serve up static web pages. Sites require contact and order forms, user login facilities, administrative interfaces and the like, functions that can't be provided by using a markup language alone.

One way of providing this kind of interactivity is to embed programming (or more accurately 'scripting') code into a web page. This code is used to process visitor input and turns a static page into a genuinely 'dynamic' one, checking and sending off email forms, identifying and logging-in authorised users and interacting with databases for an endless list of tasks.

There are many scripting languages available to web developers but perhaps the most popular and easy to use of them is PHP (which, if you're interested stands for 'PHP Hypertext Pre-processor'). Wilson Web Design uses PHP because it is a powerful, stable and well-proven web programming tool which works extremely well with its open-source stable mate, the powerful MySQL database management system.

It's also what we term a 'server-side' scripting language which means there's no need to intrude on users' computers by running code (such as JavaScript) on their browsers which can have unpredictable results, especially if JavaScript has been turned off for security reasons.