This is the package signature as generated by The GnuPG. This signature identifies the party that created the package. By verifying it you are sure that the package coming from a trustworty person or organization.
Here is the package signature:
-----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.7 (GNU/Linux) iD8DBQBG1yc4qesEzEdeXBERAgoJAJsGiifD8MQViBg/Z71cwQUbZ91mRQCfcbRk GufA7Mh6ykTG27D8H44mXPA= =NTMg -----END PGP SIGNATURE-----
You can save this signature in a text file (e.g. opera-9.23-i386-1gds.tgz.asc) in the same directory where the package file (opera-9.23-i386-1gds.tgz) resides and you can verify it by issuing the following command:
gpg --verify opera-9.23-i386-1gds.tgz.asc
NOTE: You need to import the public key of SlackPack first:
gpg --import KEY