What Files Comprise ramdisk.gz?

I am confused. I am trying to build my very first sd card for my Beagleboard. I am trying to follow this validation procedure:

http://code.google.com/p/beagleboard/wiki/BeagleboardRevCValidationv2

and I'm wondering how to identify what is the ramdisk.

In this website: http://www.angstrom-distribution.org/demo/beagleboard/

which file is the equivalent of the ramdisk.gz?
which file is the equivalent of boot.scr?