The concept of "Indirect Addressing" can most easily be understood in the guise of a "Dispatcher at a Cab Service".
In the early days of Telephone, but before the days of Radio, a client would call the Cab Company and ask for a Cab to come, or go, to such-n-such address to pick up someone or something.
When he was available, the Cab Driver would report to the dispatcher at the "home address". The dispatcher would then provide the address for the driver's next pick-up. The "home address" was the address of the dispatcher back at the Cab Company. At that address, Louie DePalma, the dispatcher, would give the cabbie the address of his next pick-up.
The cabbie would always go to the dispatcher to find the address of his next pick-up. This is "indirect addressing"... the cabbie would go to the "home address" to get the address of his next next pick-up.
I've always wanted to describe this in terms of a beer truck making a delivery. That idea applies if you consider the "something" as beer!
