Installation of PHP 5 via command line.
Reason I prefer command line interface here is because of many functions do not work properly when done via a browser interface. Like from the Webmin Command line.

On the other hand the Slicehost.com browser based command console can be used without any issues as shown throughout this tutorial.

The above command is installing quite a few packages and the related dependencies will be downloaded automatically.

---I got 166 packages that need to be installed.

Accept install: y

That’s pretty much it for PHP install and for it to work with most popular database MySQL.
(The package 'php-mysql' in the above command line is the connector for php-MySQL.  This is what makes php communicate with the MySQL database.)

One setting that MIGHT need to be enabled in php.ini to accept global variables.  It’s a security issue but some old codes out there might not work if not turned on.