I’m excited to publish my debut memoir this October 28th! I have also written two technical books:”The vi Users Handbook” and “Portable C Software”.


Trailblazer: Lighting the Path for Transgender Equality in Corporate America

“Mary Ann Horton changed how we communicate, pushed companies to add gender identity and gender expression to non-discrimination policies, and fought for transgender health care.” – The Daily Beast

To have invented the email attachment is one thing. To have done so while transitioning from male to female and paving the way for Trans rights in the workplace is quite another. Trailblazer is a brave and powerful memoir that is both touching and thought-provoking and absolutely worth the read for those who care about equality.

As a child, Mark Horton loved wearing women’s clothes. Short denim skirts, high heels, anything that made him feel like a woman. As he grew, he hid his proclivities in favor of a more traditional home and work life. But soon the question “who am I, really” was too loud and Mark began to make room for Mary Ann.

In her award-winning memoir, Mary Ann Horton recounts her search for her true self and reveals the intimate details, both professional and personal, of her transition from male to female. From navigating the dissolution of her marriage to parenting young boys, to “coming out” to coworkers, Mary Ann balanced both her responsibilities and staying true to herself. But not without struggle. She would quickly learn the challenges and heartbreak that came with navigating the maze of social, medical and legal rights afforded, or rather not afforded to the Trans community.

As Mary Ann fully became Mary Ann, her voice grew and with it a commitment to advocacy and activism. Aided by her indomitable spirit, Mary Ann became a powerful force for the acceptance of transgender benefits and rights, first at Lucent Technologies, blazing the trail for corporate America to follow.

Winner: The BookFest Awards

  • Nonfiction > Professional Memoir (1st place)
  • Nonfiction > LGBTQ+ (1st place)
  • Nonfiction > Business Leadership – Harassment & Discrimination (1st place)

Portable C Software

This 1990 book was the first published in my own name. It was a reference book showing software developers how to write their programs to be easily ported to different computer systems, and which functions were available on which systems. It is now considered a rare book, with a new copy on Amazon going for over $3,000, and used copies at $100 and up.

The vi Users Handbook

Tech writer Morris Bolsky contacted me in 1984 to help write a “quick guide” to the UNIX vi editor. We agreed to co-author it. I worked with him, providing the detailed content, and he did the editing and publication work. I was shocked to see that he listed himself as the sole author.


What is a Domain?

I wrote this paper in 1984 to publicize the concept of Internet domains. At the time the network landscape was flat, with computer names defined by the path to get an email message to them: ucbvax!research!unc!smb. This, plus the eventual availability of Internet domains through the UUCP Project, helped get everyone speaking the same user@domain.com language. It was published as: (Horton, M. What is a Domain? Proceedings of the Summer 1984 USENIX Conference, USENIX Association, Berkeley, CA, June 1984, pp. 368–372.)

Internet Standard RFC 976

Having a written standard for email formatting of messages sent over the UUCP network helped resolve differences in implementations and make it practical to use domain name syntax in UUCP email.

Internet Standard RFC 850

Usenet was one of the first Social Media networks. This document was the standard format for Usenet messages.

Transgender Demographics and Health Benefit Costs

In 2001 I performed research into how many transgender people were seeking surgeries, and what it would cost. The resulting two papers tell us


In 2004, in response to the passage of Ohio Issue 4, I sat down with my friends Lisa and Bill Koontz to write a poem about gay marriage: “How the Grinch Stole Marriage“.


Transgender 101

I’ve given this 90 minute workshop in man workplaces, churches, and other settings.

Transgender Issues in the Workplace

This advanced talk presents simple solutions employers can implement to help transgender workers be fully productive in the workplace.

The Cost of Transgender Health Benefits

This 90 minute workshop was presented at Out & Equal from about 2004 through 2008. It takes the dry statistical information from my Transgender Health Benefits papers and present is in a fun, interactive format. Here is the Powerpoint from the workshop.