Visiting Lecturer Amazes

New technology is nothing to be afraid of.

Just ask Brian W. Kernighan, the visiting lecturer for Computer Science 50, "Introduction to Computer Science" this fall.

Kernighan, one of the foremost experts in the field of computer science, didn't even see a computer until his sophomore year of college in Toronto.

"[I thought computing was] fun, new and interesting," he says.

His initial enthusiasm never waned and he continued studying computer science in graduate school at Princeton.

"I think it's more or less by accident that I went to Princeton for graduate school and kept doing it," he says.

Today, Kernighan is widely recognized as one of the geniuses behind C, the programming language taught in CS 50.

Kernighan co-authored The C-Programming Language, which was first published in 1978. The book, written with Dennis M. Ritchie '63, details the C programming language, arguably the most popular programming language today.

Although Ritchie invented the language, Kernighan helped him compile it into a comprehensive users' guide which is known among computer programmers as the "C Bible."

His authorship of the book helped land him a spot at Harvard this year as a visiting professor of computer science.

And with his enthusiasm, humor and creative antics, Kernighan has quickly become a favorite among Harvard students.

A Short Road

When McKay Assistant Professor of Computer Science Margo I. Seltzer '83, who has taught CS 50 for the past three years, accepted a fellowship offer this year, she needed to find someone to teach the course in her absence.

Seltzer turned to Kernighan, whose book is the standard in the field and Seltzer's class.

When Seltzer called Kernighan to ask if he would teach CS 50 for her this year, Kernighan says he did not realize what he was getting himself into by saying yes.

The increase in enrollment--to 430 from 323 last year--and the new teaching experience has made the course very time-consuming for Kernighan.

"Rather foolishly, perhaps, I said, 'Yeah. Why not? It sounds like fun,'" Kernighan says. "I hadn't realized how much work it was [going to be], but boy, is it fun."

"I'm glad I'm not doing all the things that a regular professor has to do," Kernighan says.

Although Kernighan says he underestimated how much time would go into the class, students and TFs agree that Kernighan does not let the demands of the job deter his enthusiasm.

"His enthusiasm is really infectious," says Ping Tjin Thum '00, a student in the class.

"I think he's really good, really funny and he's taking the job really seriously," says TF Mike Walfish '98. "I think that he is a great teacher."

Students say they are amazed at his ability to maintain his level of enthusiasm for such a large lecture class.

"It's hard to put a finger on it because it's not as though he has some formula for what he does, he's just a very charming guy and stays that way before a class of 400," says Samuel J. Klein '99.

Kernighan has also won over students with various antics ranging from cutting off part of his beard while following commands from his class to having candy thrown out to the audience for asking and answering questions.

Students and TFs praise Kernighan for not being afraid to admit his mistakes.

"He's very close to the subject matter," says Yuval Segal '97, a CS 50 TF. "[But he's] not afraid to admit that he doesn't know certain things."

"If he makes a mistake, he'll laugh at himself," Thum says. "He shows he's very human like the rest of us and making mistakes in [his] code will be inevitable so we all feel much better about that."

Kernighan does not let the mistakes slow him down, students say.

"He never loses himself when he makes a slip," says CS 50 student Samuel Klein.

Packed Lectures

Students say Kernighan's enthusiasm has played a major role in keeping the lecture hall full despite the class' 10 a.m. slot on Monday, Wednesday and Fridays.

"He's done a marvelous job keeping what could potentially dry subject material interesting," says Brad D.D. Leupen '97, a TF for CS 50. "He's just very nice and one of the most accessible men I've ever talked to."

Kernighan's most important task in teaching CS 50 is to convey the intricacies of the C programming language.

"Programming language is very specific to instructing a computer to do a particular structure of a sequence," Kernighan says. "It's the very way you tell the machine what you want it to do."

"Like any language, it has rules of grammar and rules of how you create legal sentences," he says. "This language is very precise."

Kernighan says he tries to encourage questions during lecture because he believes that is the way to make people learn.

"I try very hard to answer questions," he says. "It's what makes the class interesting. Otherwise [students] would be bored out of their minds."

Kernighan says one of the significant difficulties he has to deal with in the class is that students with a wide range of computer backgrounds are taking CS 50 since there is no other introductory computer science class.

He says he deals with the various levels of experience the best way he can.

"I try to cover what I think is important, and some of that is an enormous amount of detail," Kernighan says.

He says he could not get through the course without the help of the TFs.

"The other thing that makes the course work are the TFs," he says. "They are astonishing."

Credit Where Credit is Due

Since his arrival at Harvard, Kernighan says he has noticed that he has received a great deal of attention.

"As far as I can tell, everybody is giving me more credit than I deserve," Kernighan says.

But this "undue" credit has worked to his advantage.

Walfish recalls an incident when he was the TF on duty one night when the network went down in the terminal room.

"All these students were upset," Walfish says. "And then Professor Kernighan walks in."

Walfish and Kernighan went to the Harvard Arts and Sciences Computer Services (HASCS) office together to try to get the network fixed.

They asked for the director of HASCS, who was not there. Upon telling the FAS worker that the network was down, the worker asked skeptically how they knew that.

"How do you know," Walfish says the worker asked. "Do you work for FAS Computer Services?"

"Just as I'm about to explain how I know, Professor Kernighan said very modestly, 'Uh, no, he works for me. I'm Brian Kernighan and introduces himself,'" Walfish says.

"Once they realized who he was and that he was a professor for a course here," Walfish says, "the FAS worker, and everyone else at HASCS who was on duty, was very obliging."

Walfish says Kernighan was then taken into the computer room.

"They cleared him through like three levels of security. They fixed the problem quickly," he says.

Background

Despite his widely acclaimed teaching ability, Kernighan has not always been in academics.

Since 1969, he has been doing research at Bell Labs in New Jersey.

The labs investigate the two types of problems that arise with computers, he says. First, machines are too hard to use. Second, they are too hard to program.

"When machines are unfriendly, it's because the machine isn't programmed right," he says.

Kernighan specifically focuses on the first problem and works on improving interfaces on computers to make them easier to use.

"Most of what I have been doing in the last couple of years are user interfaces," he says.

Kernighan says that although there are many rapid changes in the world of computer science nowadays, the basics of computer technology do not vary by much.

"You still have to learn the details, but I think the underpinnings are pretty much the same," he says.CrimsonZach Levenich

When Seltzer called Kernighan to ask if he would teach CS 50 for her this year, Kernighan says he did not realize what he was getting himself into by saying yes.

The increase in enrollment--to 430 from 323 last year--and the new teaching experience has made the course very time-consuming for Kernighan.

"Rather foolishly, perhaps, I said, 'Yeah. Why not? It sounds like fun,'" Kernighan says. "I hadn't realized how much work it was [going to be], but boy, is it fun."

"I'm glad I'm not doing all the things that a regular professor has to do," Kernighan says.

Although Kernighan says he underestimated how much time would go into the class, students and TFs agree that Kernighan does not let the demands of the job deter his enthusiasm.

"His enthusiasm is really infectious," says Ping Tjin Thum '00, a student in the class.

"I think he's really good, really funny and he's taking the job really seriously," says TF Mike Walfish '98. "I think that he is a great teacher."

Students say they are amazed at his ability to maintain his level of enthusiasm for such a large lecture class.

"It's hard to put a finger on it because it's not as though he has some formula for what he does, he's just a very charming guy and stays that way before a class of 400," says Samuel J. Klein '99.

Kernighan has also won over students with various antics ranging from cutting off part of his beard while following commands from his class to having candy thrown out to the audience for asking and answering questions.

Students and TFs praise Kernighan for not being afraid to admit his mistakes.

"He's very close to the subject matter," says Yuval Segal '97, a CS 50 TF. "[But he's] not afraid to admit that he doesn't know certain things."

"If he makes a mistake, he'll laugh at himself," Thum says. "He shows he's very human like the rest of us and making mistakes in [his] code will be inevitable so we all feel much better about that."

Kernighan does not let the mistakes slow him down, students say.

"He never loses himself when he makes a slip," says CS 50 student Samuel Klein.

Packed Lectures

Students say Kernighan's enthusiasm has played a major role in keeping the lecture hall full despite the class' 10 a.m. slot on Monday, Wednesday and Fridays.

"He's done a marvelous job keeping what could potentially dry subject material interesting," says Brad D.D. Leupen '97, a TF for CS 50. "He's just very nice and one of the most accessible men I've ever talked to."

Kernighan's most important task in teaching CS 50 is to convey the intricacies of the C programming language.

"Programming language is very specific to instructing a computer to do a particular structure of a sequence," Kernighan says. "It's the very way you tell the machine what you want it to do."

"Like any language, it has rules of grammar and rules of how you create legal sentences," he says. "This language is very precise."

Kernighan says he tries to encourage questions during lecture because he believes that is the way to make people learn.

"I try very hard to answer questions," he says. "It's what makes the class interesting. Otherwise [students] would be bored out of their minds."

Kernighan says one of the significant difficulties he has to deal with in the class is that students with a wide range of computer backgrounds are taking CS 50 since there is no other introductory computer science class.

He says he deals with the various levels of experience the best way he can.

"I try to cover what I think is important, and some of that is an enormous amount of detail," Kernighan says.

He says he could not get through the course without the help of the TFs.

"The other thing that makes the course work are the TFs," he says. "They are astonishing."

Credit Where Credit is Due

Since his arrival at Harvard, Kernighan says he has noticed that he has received a great deal of attention.

"As far as I can tell, everybody is giving me more credit than I deserve," Kernighan says.

But this "undue" credit has worked to his advantage.

Walfish recalls an incident when he was the TF on duty one night when the network went down in the terminal room.

"All these students were upset," Walfish says. "And then Professor Kernighan walks in."

Walfish and Kernighan went to the Harvard Arts and Sciences Computer Services (HASCS) office together to try to get the network fixed.

They asked for the director of HASCS, who was not there. Upon telling the FAS worker that the network was down, the worker asked skeptically how they knew that.

"How do you know," Walfish says the worker asked. "Do you work for FAS Computer Services?"

"Just as I'm about to explain how I know, Professor Kernighan said very modestly, 'Uh, no, he works for me. I'm Brian Kernighan and introduces himself,'" Walfish says.

"Once they realized who he was and that he was a professor for a course here," Walfish says, "the FAS worker, and everyone else at HASCS who was on duty, was very obliging."

Walfish says Kernighan was then taken into the computer room.

"They cleared him through like three levels of security. They fixed the problem quickly," he says.

Background

Despite his widely acclaimed teaching ability, Kernighan has not always been in academics.

Since 1969, he has been doing research at Bell Labs in New Jersey.

The labs investigate the two types of problems that arise with computers, he says. First, machines are too hard to use. Second, they are too hard to program.

"When machines are unfriendly, it's because the machine isn't programmed right," he says.

Kernighan specifically focuses on the first problem and works on improving interfaces on computers to make them easier to use.

"Most of what I have been doing in the last couple of years are user interfaces," he says.

Kernighan says that although there are many rapid changes in the world of computer science nowadays, the basics of computer technology do not vary by much.

"You still have to learn the details, but I think the underpinnings are pretty much the same," he says.CrimsonZach Levenich