Fernando José "Corby" Corbató (July 1, 1926 – July 12, 2019) was a prominent American computer scientist, notable as a pioneer in the development of

time-sharing In computing, time-sharing is the sharing of a computing resource among many users at the same time by means of multiprogramming and multi-tasking.DEC Timesharing (1965), by Peter Clark, The DEC Professional, Volume 1, Number 1 Its emergence ...

operating system An operating system (OS) is system software that manages computer hardware, software resources, and provides common services for computer programs. Time-sharing operating systems schedule tasks for efficient use of the system and may also i ...

Career

Corbató was born on July 1, 1926 in

Oakland, California Oakland is the largest city and the county seat of Alameda County, California, United States. A major West Coast of the United States, West Coast port, Oakland is the largest city in the East Bay region of the San Francisco Bay Area, the third ...

, to Hermenegildo Corbató, a Spanish literature professor from

Villarreal Villarreal ( ca-valencia , Vila-real) is a city and municipality in the province of Castellón which is part of the Valencian Community in the east of Spain. The town is located at 42 m above sea level, 7 km to the south of the province's ...

Spain , image_flag = Bandera de España.svg , image_coat = Escudo de España (mazonado).svg , national_motto = ''Plus ultra'' (Latin)(English: "Further Beyond") , national_anthem = (English: "Royal March") , i ...

, and Charlotte (née Carella Jensen) Corbató. In 1930 the Corbató family moved to

Los Angeles Los Angeles ( ; es, Los Ángeles, link=no , ), often referred to by its initials L.A., is the List of municipalities in California, largest city in the U.S. state, state of California and the List of United States cities by population, sec ...

for Hermenegildo's job at the

University of California, Los Angeles The University of California, Los Angeles (UCLA) is a public land-grant research university in Los Angeles, California. UCLA's academic roots were established in 1881 as a teachers college then known as the southern branch of the California S ...

. In 1943, Corbató enrolled at UCLA, but due to

World War II World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the vast majority of the world's countries—including all of the great powers—forming two opposing ...

he was recruited by the

Navy A navy, naval force, or maritime force is the branch of a nation's armed forces principally designated for naval and amphibious warfare; namely, lake-borne, riverine, littoral, or ocean-borne combat operations and related functions. It in ...

during his first year. During the war, Corbató "debug edan incredible array of equipment", inspiring his future career. Corbató left the Navy in 1946, enrolled at the

California Institute of Technology The California Institute of Technology (branded as Caltech or CIT)The university itself only spells its short form as "Caltech"; the institution considers other spellings such a"Cal Tech" and "CalTech" incorrect. The institute is also occasional ...

, and received a bachelor's degree in physics in 1950. He then earned a PhD in

physics Physics is the natural science that studies matter, its fundamental constituents, its motion and behavior through space and time, and the related entities of energy and force. "Physical science is that department of knowledge which r ...

from the

Massachusetts Institute of Technology The Massachusetts Institute of Technology (MIT) is a private land-grant research university in Cambridge, Massachusetts. Established in 1861, MIT has played a key role in the development of modern technology and science, and is one of the ...

in 1956. He joined MIT's Computation Center immediately upon graduation, became a professor in 1965, and stayed at MIT until he retired. The first time-sharing system he was associated with was known as the MIT Compatible Time-Sharing System (CTSS), an early version of which was demonstrated in 1961. Corbató is credited with the first use of

password A password, sometimes called a passcode (for example in Apple devices), is secret data, typically a string of characters, usually used to confirm a user's identity. Traditionally, passwords were expected to be memorized, but the large number of ...

s to secure access to files on a large computer system, though he later claimed that this rudimentary security method had proliferated and became unmanageable. The experience with developing CTSS led to a second project,

Multics Multics ("Multiplexed Information and Computing Service") is an influential early time-sharing operating system based on the concept of a single-level memory.Dennis M. Ritchie, "The Evolution of the Unix Time-sharing System", Communications of ...

, which was adopted by

General Electric General Electric Company (GE) is an American multinational conglomerate founded in 1892, and incorporated in New York state and headquartered in Boston. The company operated in sectors including healthcare, aviation, power, renewable en ...

for its high-end computer systems (later acquired by

Honeywell Honeywell International Inc. is an American publicly traded, multinational conglomerate corporation headquartered in Charlotte, North Carolina. It primarily operates in four areas of business: aerospace, building technologies, performance ma ...

). Multics pioneered many concepts now used in modern operating systems, including a hierarchical file system, ring-oriented security,

access control list In computer security, an access-control list (ACL) is a list of permissions associated with a system resource (object). An ACL specifies which users or system processes are granted access to objects, as well as what operations are allowed on gi ...

single-level store Single-level storage (SLS) or single-level memory is a computer storage term which has had two meanings. The two meanings are related in that in both, pages of memory may be in primary storage (RAM) or in secondary storage (disk), and that the ph ...

dynamic linking In computing, a dynamic linker is the part of an operating system that loads and links the shared libraries needed by an executable when it is executed (at " run time"), by copying the content of libraries from persistent storage to RAM, filling ...

, and extensive on-line reconfiguration for reliable service. Multics, while not particularly commercially successful in itself, directly inspired

Ken Thompson Kenneth Lane Thompson (born February 4, 1943) is an American pioneer of computer science. Thompson worked at Bell Labs for most of his career where he designed and implemented the original Unix operating system. He also invented the B programmi ...

to develop

Unix Unix (; trademarked as UNIX) is a family of multitasking, multiuser computer operating systems that derive from the original AT&T Unix, whose development started in 1969 at the Bell Labs research center by Ken Thompson, Dennis Ritchie, an ...

, the direct descendants of which are still in extremely wide use; Unix also served as a direct model for many other subsequent operating system designs.

Awards

Among many awards, Corbató received the

Turing Award The ACM A. M. Turing Award is an annual prize given by the Association for Computing Machinery (ACM) for contributions of lasting and major technical importance to computer science. It is generally recognized as the highest distinction in comput ...

in 1990, "for his pioneering work in organizing the concepts and leading the development of the general-purpose, large-scale, time-sharing and resource-sharing computer systems". In 2012, he was made a Fellow of the Computer History Museum "for his pioneering work on timesharing and the Multics operating system".

Legacy

Corbató is sometimes known for "Corbató's Law" which states: :The number of lines of code a programmer can write in a fixed period of time is the same, independent of the language used. Corbató is recognized as helping to create the first computer password.

Personal life and death

Corbató married programmer Isabel Blandford in 1962; she died in 1973. Corbató had a second wife, Emily (née Gluck); two daughters, Carolyn Corbató Stone and Nancy Corbató, by his late wife Isabel; two step-sons, David Gish and Jason Gish; a brother, Charles; and five grandchildren. Corbató lived on Temple Street in West Newton, MA. He died on July 12, 2019 in Newburyport, Massachusetts, at the age of 93 due to complications from

diabetes Diabetes, also known as diabetes mellitus, is a group of metabolic disorders characterized by a high blood sugar level ( hyperglycemia) over a prolonged period of time. Symptoms often include frequent urination, increased thirst and increased ...

Publications

* F. J. Corbató, M. M. Daggett, R. C. Daley,
An Experimental Time-Sharing System
' (IFIPS 1962) is a good description of CTSS * F. J. Corbató (editor),
The Compatible Time-Sharing System: A Programmer's Guide
' (M.I.T. Press, 1963) * F. J. Corbató, V. A. Vyssotsky

(

AFIPS The American Federation of Information Processing Societies (AFIPS) was an umbrella organization of professional societies established on May 10, 1961, and dissolved in 1990. Its mission was to advance knowledge in the field of information science, ...

1965) is a good introduction to Multics * * F. J. Corbató, C. T. Clingen, J. H. Saltzer
''Multics -- The First Seven Years''
(AFIPS, 1972) is an excellent review, after a considerable period of use and improvement * F. J. Corbató, C. T. Clingen,

' ("Conference on Research Directions in Software Technology", Providence, Rhode Island, 1977) is a fascinating look at what it was like to manage such a large software project * F. J. Corbató,
On Building Systems That Will Fail
' (Turing Award Lecture, 1991) * F. J. Corbató,
A paging experiment with the Multics system
'. Included in a Festschrift published in honor of Prof. P.M. Morse. MIT Press, Cambridge, Mass., 1969.

References

External links

Oral history interview with Fernando J. Corbató
at

Charles Babbage Institute The IT History Society (ITHS) is an organization that supports the history and scholarship of information technology by encouraging, fostering, and facilitating archival and historical research. Formerly known as the Charles Babbage Foundation, ...

, University of Minnesota. Corbató discusses computer science research, especially time-sharing, at the Massachusetts Institute of Technology (MIT).
Oral history interview with Fernando J. Corbató
at the Computer History Museum in Mountain View, CA. Fernando Corbató reviews his early educational and naval experiences in the Eddy program during World War II, including the Compatible Time-Sharing System (CTSS), Project MAC, and Multics.
Computer Networks: The Heralds of Resource Sharing
documentary ca. 1972 about the

ARPANET The Advanced Research Projects Agency Network (ARPANET) was the first wide-area packet-switched network with distributed control and one of the first networks to implement the TCP/IP protocol suite. Both technologies became the technical fou ...

. Includes footage of Fernando Corbató. * , Corbato demonstrates MIT's Compatible Time-Sharing System.
Corby
by

Tom Van Vleck Tom Van Vleck is an American computer software engineer. Life and work Van Vleck graduated from MIT in 1965 with a BS in Mathematics. He worked on CTSS at MIT, and co-authored its first email program with Noel Morris. In 1965, he joined Proje ...

on the

website. A background sketch that includes many further links and several photographs. *
Corby Memorial
- Transcript of the memorial held at MIT. {{DEFAULTSORT:Corbato, Fernando J. 1926 births 2019 deaths Turing Award laureates California Institute of Technology alumni Fellows of the Association for Computing Machinery MIT Department of Physics alumni Massachusetts Institute of Technology faculty Members of the United States National Academy of Engineering Multics people Time-sharing Writers from Oakland, California Military personnel from California American people of Spanish descent United States Navy personnel of World War II