The 5th Annual China PHP Conference

What is PHP?

PHP (recursive acronym for PHP: Hypertext Preprocessor) is a widely-used open source general-purpose scripting language that is especially suited for web development and can be embedded into HTML.

Nice, but what does that mean? An example:

Example #1 An introductory example

<!DOCTYPE HTML>
<html>
    <head>
        <title>Example</title>
    </head>
    <body>

        <?php
            
echo "Hi, I'm a PHP script!";
        
?>

    </body>
</html>

Instead of lots of commands to output HTML (as seen in C or Perl), PHP pages contain HTML with embedded code that does "something" (in this case, output "Hi, I'm a PHP script!"). The PHP code is enclosed in special start and end processing instructions <?php and ?> that allow you to jump into and out of "PHP mode."

What distinguishes PHP from something like client-side JavaScript is that the code is executed on the server, generating HTML which is then sent to the client. The client would receive the results of running that script, but would not know what the underlying code was. You can even configure your web server to process all your HTML files with PHP, and then there's really no way that users can tell what you have up your sleeve.

The best things in using PHP are that it is extremely simple for a newcomer, but offers many advanced features for a professional programmer. Don't be afraid reading the long list of PHP's features. You can jump in, in a short time, and start writing simple scripts in a few hours.

Although PHP's development is focused on server-side scripting, you can do much more with it. Read on, and see more in the What can PHP do? section, or go right to the introductory tutorial if you are only interested in web programming.

add a note add a note

User Contributed Notes 1 note

up
-1
tomgoldie at yahoo dot com
16 hours ago
I'm really NEW to PHP, so be gentle. But a few concepts really helped my understanding.

1) PHP is to Apache Server what OpenOffice BASIC is to OpenOffice. A way to make dynamic webpages on Apache Server. (Or maybe what VisualBasic is to Windows or to Microsoft Office...)

2) Because it is made for Apache, and Apache for it (perhaps) it is made to simplify handing data from a database to a webpage. It quickly turns database tables into arrays so you can iterate through the data in a loop, just inserting HTML tags as you go, like <li> and <br> as you go.

Sorry this is a little simplistic, but it helped me get beyond the "why?" stage.
To Top