Is it possible to install and run PHP on a USB stick?

It is possible to install and run PHP on a USB stick by using a portable server solution like XAMPP or Portable Web Server. These tools allow you to run a web server with PHP, MySQL, and Apache directly from the USB stick without the need for installation on the host computer. This way, you can carry your PHP development environment with you wherever you go.

```php
// No PHP code snippet needed for this explanation.