Question: I am new to PHP, just downloaded it, and wrote a ["Hello, World!"](https://en.wikipedia.org/wiki/%22Hello,_World!%22_program) program:

```
<html>
    <body>

    <?php
        $fileName = "test.jpg";
        $txt = "Hello, World!";
        echo $txt;
    ?>

    </body>
</html>

```

But it doesn't work. I named the file `test.php` and opened it with Firefox and nothing was displayed.

Answer: 
You'll have to pass it through a webserver of some kind, for example [IIS](http://en.wikipedia.org/wiki/Internet_Information_Services) or [Apache](http://en.wikipedia.org/wiki/Apache_HTTP_Server), for it to work.

PHP is a server-side language, thus you can't just open the PHP file in a browser. Instead, try googling some free PHP hosts, and upload your files there.

You could for example go for these solutions that will provide you with what you need:

* WAMP - <http://www.wampserver.com/en/> (Windows)
* XAMPP - <http://www.apachefriends.org/en/xampp.html> - (Windows, Mac, and Linux)

Those solutions will install Apache, [MySQL](http://en.wikipedia.org/wiki/MySQL) and PHP and allow you to play locally with PHP development. Later on, if you want to deploy your code, you will have to find an external host (or host it on your own computer).
Do you have a local server installed? PHP is a server-side scripting language, so it cannot just be run like a normal HTML file.

Try watching the first few videos on the [New Boston's PHP series](http://thenewboston.org/list.php?cat=11). They show you simply how to download, install and use a local server to run your PHP on.