Alfred Aho facts for kids

Alfred Vaino Aho (born August 9, 1941) is a famous Canadian computer scientist. He is well-known for his work on programming languages and compilers. Compilers are special programs that turn code written by humans into instructions computers can understand.

Alfred Aho also wrote many important textbooks about computer programming. These books teach people how to design and build computer programs. He was chosen to be part of the National Academy of Engineering in 1999. This was because of his great work on computer algorithms and programming tools.

In 2020, Alfred Aho and his friend Jeffrey Ullman won the Turing Award. This award is like the Nobel Prize for computer science. It is the highest honor a computer scientist can receive.

Alfred Aho's Career Journey

Alfred Aho studied Engineering Physics at the University of Toronto. He earned his first degree there in 1963. Later, he went to Princeton University. He received his master's degree in 1965 and his PhD in 1967. His PhD was in Electrical Engineering and Computer Science.

After finishing his studies, Aho worked at Bell Labs. This was a famous research company. He worked there from 1967 to 1991. He also returned to Bell Labs from 1997 to 2002. During his second time there, he was a Vice President.

Since 1995, he has been a professor at Columbia University. He teaches Computer science there. He was also the head of the computer science department for a few years.

Early Research and Algorithms

For his PhD, Aho created new ways to understand computer languages. He developed "indexed grammars" and "nested-stack automatons." These ideas helped to make computer languages more powerful. They also kept them easy to work with.

At Bell Labs, Aho created fast ways to search for text patterns. He used these methods in early versions of Unix tools. These tools were called egrep and fgrep. The fgrep method is now known as the Aho–Corasick algorithm. It is used in many search systems today.

Aho worked with other smart people like Steve Johnson and Jeffrey Ullman. They created efficient ways to analyze and translate programming languages. Steve Johnson used Aho's ideas to create a tool called yacc. This tool helps build the "syntax analyzer" part of a compiler.

Another tool called lex was also created using Aho's ideas. Lex helps build the "lexical analyzer" part of a compiler. Together, lex and yacc have been used to create many parts of modern programming language compilers.

Famous "Dragon Books"

Aho and Ullman wrote several important textbooks about compilers. Their 1977 book, Principles of Compiler Design, had a green dragon on its cover. People started calling it "the green dragon book."

In 1986, they updated the book with Ravi Sethi. This new version was called "the red dragon book." It even appeared briefly in the movie Hackers. In 2006, Monica Lam joined them for another update. This became "the purple dragon book."

These "dragon books" are used in universities all over the world. They are also important guides for people working in the computer industry.

Other Key Books and AWK

In 1974, Aho, John Hopcroft, and Ullman wrote The Design and Analysis of Computer Algorithms. This book helped make algorithms and data structures a main part of computer science studies. It was cited by many other computer scientists for decades.

Alfred Aho is also famous for helping create the AWK programming language. He worked on it with Peter J. Weinberger and Brian Kernighan. The "A" in AWK stands for "Aho."

Today, Aho is still interested in programming languages, compilers, and algorithms. He also studies quantum computing. He is part of a research group at Columbia University. His work has been cited over 81,000 times by other researchers.

Awards and Honors

Alfred Aho has received many important awards. He won the IEEE's John von Neumann Medal. He is also a member of the National Academy of Engineering and the National Academy of Sciences.

He has received honorary doctorates from several universities. These include the University of Waterloo, the University of Helsinki, and the University of Toronto. He is also a Fellow of many important organizations. These include the American Association for the Advancement of Science, ACM, Bell Labs, and IEEE.

In 2017, Aho, Hopcroft, and Ullman won the C&C Prize. This award is given by the NEC Corporation. Most recently, he and Ullman were given the 2020 Turing Award in March 2021.

Personal Life and Teaching

Alfred Aho has been teaching at Columbia University in New York City since 1995. He is a very popular teacher. In 2003, he won the Great Teacher Award from the Society of Columbia Graduates.

Books

Alfred Aho has written or co-written many influential books in computer science. Some of his well-known books include:

• A. V. Aho and J. D. Ullman, The Theory of Parsing, Translation, and Compiling, Vol. 1, Parsing. Prentice Hall, 1972.
• A. V. Aho and J. D. Ullman, Principles of Compiler Design. Addison-Wesley, 1977.
• A. V. Aho, J. E. Hopcroft, J. D. Ullman, Data Structures and Algorithms. Addison-Wesley, 1983.
• A. V. Aho, R. Sethi, J. D. Ullman, Compilers: Principles, Techniques, and Tools. Addison-Wesley, Reading MA 1986.
• A. V. Aho, B. W. Kernighan, and P. J. Weinberger, The AWK Programming Language. Addison-Wesley, 1988.
• A. V. Aho, M. S. Lam, R. Sethi, and J. D. Ullman, Compilers: Principles, Techniques, and Tools, Second Edition. Addison-Wesley, 2007.

See also

In Spanish: Alfred Aho para niños