[4] Barr received a BS in Applied Physics (with honors) at North Carolina State University in 1962, during which time he began an assistantship at the NCSU Computing Center.

[5] Barr was named 1995 Distinguished Alumnus, North Carolina State University, College of Physical and Mathematical Sciences.

[5] In 1966, Barr began working on the SAS System, a family of statistical analysis software used in data management, machine learning and analytics.

[6] In September 1966, Barr presented the conceptual ideas of SAS to members of the Committee on Statistical Software of the University Statisticians of the Southern Experiment Stations (USSES) in Athens, Georgia.

[7] Barr had earlier created an analysis-of-variance modeling language inspired by the notation of statistician Maurice Kendall.

[7] In 1968, Barr began collaborating with other programmers,[9] most prominently James Goodnight, a student at North Carolina State University who became a co-leader of the project and developed procedures for general linear modelling for the system.

Implemented on the Data General Nova minicomputer, the program became the Singer Corporation Remote Batch Terminal.

[16] In 1983, Barr developed hardware and software for performing HASP remote job entry communication on the IBM PC.

[20] Assigned to work with the National Military Command Center, the information processing branch of the Joint Chiefs of Staff, Barr rewrote and enhanced FFS, implementing three of its five major components: retrieval, sorting, and file update.