gnus-select-method

gnus-select-method is a variable defined in `gnus.el'.
Its value is

(nntp "news")

Documentation:
Default method for selecting a newsgroup.
This variable should be a list, where the first element is how the
news is to be fetched, the second is the address.

For instance, if you want to get your news via "flab.flab.edu" using
NNTP, you could say:

(setq gnus-select-method '(nntp "flab.flab.edu"))

If you want to use your local spool, say:

(setq gnus-select-method (list 'nnspool (system-name)))

If you use this variable, you must set `gnus-nntp-server' to nil.

There is a lot more to know about select methods and virtual servers -
see the manual for details.

You can customize this variable.