Hi Owen ..
Yes it is ....
What they're referring to of course, is the Prostate Gland ... this can be stimulated internally as well as externally ..
To do it internally, try lying on your back or side, with your knees drawn up towards your chest .. insert a well lubed finger into the Anus (to about the first joint) then feel for a "walnut" sized lump .. that's your Prostate ... simply massage it .. you could try a "come here" type gesture with the index finger (or get your partner to do it for you) .. it's fantastic ..
The external method is by feeling around at the base of the Penis (behind the Scrotum) and just in front of the Anus (that bit is called the Perineum) until you find the "walnut" .. then just do whatever feels pleasurable ...
As an alternative to "ordinary" Masturbation it's a lovely change .. and to get a loving partner to help out can be very erotic (I believe this is known as Prostate "milking") ...
Hope this has helped answer your question ..
Bye for now,
Orion ..