\documentclass[dvips, letterpaper]{article}
\usepackage[centering,width=7in,height=9.5in,includefoot]{geometry}% geometry v3; for v2, use: [width=7in,height=9.5in,nohead]
\usepackage[parfill]{parskip}
\usepackage{amsmath, array, theorem}
\pagestyle{empty}
\let\epsilon\varepsilon
\let\phi\varphi
\begin{document}

\subsubsection*{Initializing}
Interactively generate my key: \texttt{gpg --gen-key}\\
List all public keys I have: \texttt{gpg --list-keys}\\
Generate a ``violated key'' message: \texttt{gpg --output revokedkey.asc --gen-revoke 0x}\textsl{key\_num}

\subsubsection*{Encrypting}
Encrypt using their public key (and sign it):\\
\phantom{Menace} \texttt{gpg --recipient their\_username --sign --encrypt file}\\
Encrypt using a passphrase: \texttt{gpg --symmetric filename}

\subsubsection*{Decrypting}
Decrypt a file: \texttt{gpg --decrypt filename}\\
Decrypt STDIN: \texttt{gpg --decrypt}

\subsubsection*{Signing}
Sign a message: \texttt{gpg --clearsign filename}\\
Sign a message in separarte file: \texttt{gpg --detach-sign filename}

Verifying: \texttt{gpg --verify signedfile}\\
\phantom{Verifying: }\texttt{gpg --verify signedfile.sig signedfile}

\subsubsection*{Keyrings}
Export a/my public key: \texttt{gpg --armor --export username $>$ keyname.asc}\\
Import someone else's public key: \texttt{gpg --import user-key.asc}

Get public key from a public key server:\\
\phantom{Menace} \texttt{gpg --recv-keys --keyserver wwwkeys.pgp.net user@some-email.com}\\
Send a/my public key to a public key server:\\
\phantom{Menace} \texttt{gpg --send-keys --keyserver wwwkeys.pgp.net user@some-email.com}

\subsubsection*{Approving} Verifying that someone else's key is
correct. Typically involves talking to them directly to verify that
the public key you have is the one they sent.

Command line: \texttt{gpg --sign-key keyID}\\
Interactive, more powerful/flexible: \texttt{gpg --edit-key keyID}

\subsubsection*{Restricting to ASCII}
\texttt{gpg --armor --recipient username --sign --encrypt filename}\\
\texttt{gpg --armor --symmetric filename}\\
\texttt{gpg --armor --sign message}

\end{document}