Using PGP to Verify Digital Signatures
Because most of our constituents receive documents that are signed with the CERT/CC PGP key, we focus on the second use. In this paper, we provide some background information about PGP and explain how to check signatures for validity.
A PGP signature appears as a block of seemingly random letters and numbers at the end of the text. A valid digital signature tells the reader of the document that it was written by the owner of the PGP key and the text hasn't been changed in any way since it was signed."