Mary Ann Horton

Mary Ann Horton (born Mark R. Horton, on November 21, 1955), is a Usenet and Internet pioneer.

Finding an interest in computer programming in 1970, Horton moved to San Diego County in 1971, and quickly fell in love with California.

She graduated from San Dieguito High School in 1973.

Earning a BSCS from the University of Southern California in 1976, Horton went on to obtain an MSCS at the University of Wisconsin, and transfer to the University of California at Berkeley in 1978, earning a PhD in Computer Science in 1981.

Horton was introduced to UNIX at Wisconsin, creating an enhanced UNIX text editor called hed.

At Berkeley, she contributed to the development of Berkeley UNIX, including the vi text editor, uuencode (the first mechanism for binary Email attachments), w and load averages, termcap, and curses.

Her PhD dissertation was the creation of a new type of syntax-directed editor with a textual interface.

This technology was later used to create computer-aided software engineering tools.

Horton contributed to Berkeley UNIX (BSD), including the vi editor and terminfo database, created the first email binary attachment tool uuencode, and led the growth of Usenet in the 1980s.

Horton successfully requested the first transgender-inclusive language added to the Equal Employment Policy in a large American company, and championed the language and insurance coverage of transgender health benefits at other companies.

Horton is a computer scientist and a transgender educator and activist.

Horton was born in Richland, Washington, and raised in the Pacific Northwest.

In 1980, Horton brought Usenet's A News system to Berkeley and began to champion its growth from a 10-site network.

To Usenet's original dialup UUCP technology, she added support for Berknet and ARPANET, and added a gateway between several popular ARPANET mailing lists and usenet "fa" newsgroups.

In 1981, high school student Matt Glickman asked Horton for a spring break project, and the two designed and implemented B News, which offered major performance and user interface improvements needed to keep up with the explosive growth of Usenet traffic volume.

In 1981, Horton became a Member of Technical Staff of Bell Labs in Columbus, Ohio.

At Bell Labs she brought parts of Berkeley UNIX to UNIX System V, including vi and curses; as part of the work on curses, she developed terminfo as a replacement for termcap (most of this work shipped as part of SVR2).

Horton recruited membership in and designed the original physical topology of the Usenet Backbone in 1983.

Gene "Spaf" Spafford then created an email list of the backbone administrators, plus a few influential posters.

This list became known as the Backbone Cabal and served as a "political (i.e. decision making) backbone".

The backbone ensured the reliability and performance of the overall network.

Usenet began with only a few messages per day, but volume rapidly grew to become a problem.

Horton added moderated newsgroups, distinguished with names beginning with "mod" or containing "announce", and moderated the first such newsgroup: news.announce.important.

Only the moderator could post messages, all other messages were automatically sent to the moderator for approval.

Eventually the B News software was enhanced to permit any newsgroup with any name to be moderated.

Usenet relied on email for replies, requiring that Usenet links could be used for email.

At first, all Usenet and UUCP messages used "bang paths", such as unc!research!ucbvax!mark, as email addresses.

Horton guided this email process, including the use of the ARPANET/UUCP gateway, using routed email addresses such as cbosgd!mark@berkeley.

These addresses were complex, convoluted, and sometimes ambiguous.

When Internet domains were first created in 1983, Horton championed their use, publishing the classic paper "What is a domain?"

At Usenix in January 1984, Horton recruited a group of volunteers to create the UUCP Mapping Project.

The project divided the world into geographic regions.

A volunteer for each region maintained the region's UUCP connectivity map and posted it regularly to the comp.mail.maps newsgroup.

Each site ran Steve Bellovin and Peter Honeyman's pathalias program to create a locally optimized email routing database from this map.

Horton worked with Chris Seiwald and Larry Auton to produce the smail program, used this database to route email, using email addresses such as mark@cbosgd.UUCP.

In 1987 she joined the Bell Labs Computation Center to bring official support for Usenet and Email to Bell Labs.

Horton continued to lead Usenet until 1988.

During this time she promoted rapid growth by arranging news feeds for new sites.

Each new site agreed to be the feed for two more new sites as the need arose.

This policy contributed to the growth of Usenet to over 5000 sites by 1987.