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.
Simple answer, but what does that mean? An example:
Example 1-1. An introductory example
echo "Hi, I'm a PHP script!";
Notice how this is different from a script written in other languages like Perl or C -- instead of writing a program with lots of commands to output HTML, you write an HTML script with some
embedded code to do something (in this case, output some text). The PHP code is enclosed in special start and end tags that
allow you to jump into and out of "PHP mode".
receive the results of running that script, with no way of determining what the underlying code may be. 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.