PGP stands for "Pretty Good Privacy", an encryption standard created by Phil Zimmermann, a now famous individual who faced great opposition to the adoption of strong encryption as a standard that was available to all people. You can find the official versions of PGP at www.pgp.com.
! ! There is a GNU free implementation of this same encryption called GNUPrivacy Guard, commonly referred to as GpG or GnuPG, available at http://www.gnupg.org. !!
PGP 8.0 is the first PGP version to fully support Windows XP. http://www.pgpi.org/products/pgp/versions/freeware/winxp/8.0/