PR, Potted?

[DownUnderLite]

Excuse my ignorance, but what is the difference between PR and Potted bulbs?
I already know what a bi pin bulb is, but PR ? Potted? Aren't they the same?
Can someone please explain ?

I'm finally going to try my first mod using a 5D mag as the host. (Gotta do something with this baton)

 

[Niteowl]

PR and Potted are the same, drop 'em in. Here, potted usually refers to a bi-pin that's put in a PR base.