The program 'php' is currently not installed.

ServerPilot uses its own PHP builds so you can have multiple versions of PHP on a server independent of what Ubuntu ships.

If you try to use php and get the following error:

~$ php
The program 'php' is currently not installed.  You can install it by typing:
sudo apt-get install php5-cli

Do not try to install php5-cli.

ServerPilot has installed its PHP executables named as phpX.Y-sp.

For example:

~$ php5.4-sp -v
PHP 5.4.25 (cli) (built: Feb 11 2014 02:04:13)
Copyright (c) 1997-2014 The PHP Group
Zend Engine v2.4.0, Copyright (c) 1998-2014 Zend Technologies

For more information, see What ServerPilot Installs, Why ServerPilot Installs Its Own Nginx, Apache, and PHP Packages, and How to Use the PHP CLI.