USENIX Annual Technical Conference

The USENIX Annual Technical Conference (USENIX ATC, or, canonically, USENIX) was a conference of computing researchers sponsored by the USENIX association. It was originally USENIX's flagship conference.

USENIX Annual Technical Conference
Abbreviation	USENIX ATC
Discipline	Systems research
Publication details
Publisher	USENIX
History	1975--2025
Frequency	Biannual (1975-1994) Annual (1995-2025)

History

The first official USENIX conference was organized by Mel Ferentz at CUNY in June 1975; it had approximately 40 attendees from 20 institutions.^[1] The conference evolved into a twice-yearly event, with one conference in summer and one in winter, and eventually grew to over 3,000 attendees.^[2] It had a strong practical bias and emphasized implementation;^[3] it included computing tutorials, a single-track technical session for presenting refereed research papers, Special Interest Group meetings, and BoFs. In 1995, the conference was changed to a single annual conference; hence the name.^[4]

Around the year 2000, the focus of the conference shifted more towards academic research.^[2][5] It was now seen as a prestigious venue for systems research^[6] and had an 'A' rating from the Australian CORE Conference Ranking system.^[7]

As the systems community continued to grow, a number of more specialized conferences started to appear, such as OSDI, NSDI, FAST, or USENIX Security. As a result, papers that might previously have been published at ATC began to appear at these conferences instead, and attendance at ATC started to dwindle, from 1,698 attendees in 2000 to 165 in 2024. From 2021 on, ATC was co-located with OSDI,^[3] but this was not enough to stop the decline in attendance, so USENIX decided to end the conference series in 2025, after 50 years.^[4]

Impact

Several notable announcements took place at ATC: in 1979, ONYX, the first attempt at genuine UNIX hardware, was revealed; in 1980, Jim Ellis announced Usenet; and in 1982, DEC unveiled the creation of its UNIX product.^[4] Additionally, a number of well-known UNIX systems were first presented as ATC papers, including Sendmail, NFS, Kerberos, the X Window system, Perl, Tcl, and GNOME. In 1995, James Gosling announced "Oak", which eventually became the Java Programming Language.^[1]