In this document, I try to answer some common questions about why I do some of the things that I do.

E-mail Questions

Why do you only send PDFs when I ask for a document from you?

Some other people have written better answers than I have, but the long and short of it is that Microsoft Word is not an acceptable document interchange format. This is true for several reasons:

• The Microsoft Word formats (including Office Open XML documents having extensions such as docx, xlsx, etc.) are proprietary and thus cannot be implemented by other software without significant legal risk.
• The Microsoft Word software does not work on Linux, and only partially supported on Mac OS X. Thus, using Word limits my choices in operating systems in ways that unduly constrain my ability to get work done.
• There is no single Microsoft Word format: each version has its own quirks and bugs, meaning that if you do not have the matching fontset, version and operating system, you will not receive the same document that I intended to send.
• Microsoft Word has poor support for mathematics, unlike OpenOffice.org and LaTeX. I prefer to use tools appropriate to the task at hand.

Why does everything I receive from you have a signature.asc attachment or funky text like "-----BEGIN PGP SIGNATURE-----"?

As one might guess from the word "signature," these odd habits are related to signing my e-mails and providing some sort of verification as to who actually sent them. More concretely, I use the Pretty Good Privacy (PGP) protocol as implemented by the GNU Privacy Guard software (provided with most Linux distributions, and available for Windows here) to cryptographically sign my e-mails using my private key. Only someone with both my private key and my personal passphrase can make such a signature, but due to the magic of discrete logarithms, anyone with my public key (download) can verify that my signature is legit.
If you use an e-mail client like KMail or Evolution (Windows version), PGP support is built-in, and the signature status of my e-mails should be automatically displayed. If you use the Thunderbird e-mail client, then the Enigmail extension will provide you with PGP support. For webmail users with Firefox, FireGPG adds PGP support to Firefox with special handling for Gmail.

Grammar Questions

Why did you write PDFs above instead of PDF's?

Apostrophes indicate contractions or possessives-- never pluralization.