(FORTUNE Magazine) – Computers, health care, and environmental engineering are hot now. But what was hot then? Over the three-quarters of a century that FORTUNE has been chronicling the world of big business, each decade seems to have one field that stands above the rest. Maybe it employed the most people. Maybe it made the most money. Or maybe it simply captured the public imagination like nothing else. To work in one of these fields was to be part of something much bigger than you were. It was to be a key component of the engine that drives American industry. The following images, all shot for FORTUNE, show us what that was like.

BY ELLEN FLORIAN KRATZ

1930s

CONSTRUCTION

In the depths of the Depression, F.D.R. created work for the unemployed by funding massive building projects. This shot of men toiling on the Grand Coulee Dam in Washington State ran in July 1937.

1940s

DEFENSE

For women who had never worked outside the home, World War II was life changing. Here, in 1943, Remington Arms factory workers pack machine-gun cartridge belts before shipping them to the front.

1950s

AUTOMOBILES

Good times were rolling again for American business. Flashy, muscular, Detroit-made cars--like these 1954 models from (front to rear) Plymouth, Ford, and Chevrolet--rolled along with them.

1960s

AEROSPACE

J.F.K.'s race to land a man on the moon before the end of the decade made scientists sexy. This photo, which ran in the November 1963 issue, shows Martin Marietta workers at a Denver plant trying to figure out how to maneuver a capsule in space.

1970s

MUSIC

In a decade of gas lines, stagflation, and general malaise, the music biz was a bright spot. Maurice, Barry, and Robin Gibb--three tycoons known as the Bee Gees--graced our cover on April 23, 1979, the year after the Saturday Night Fever soundtrack was the bestselling album in the country.

1980s

WALL STREET

Greed was good, leveraged buyouts were an obsession, and Henry Kravis--founding partner of legendary LBO firm Kohlberg Kravis Roberts-- was a master of the universe. This photo of him overlooking New York City's Central Park ran on April 24, 1989.

1990s

TECHNOLOGY

Steve Jobs and Bill Gates made the world safe for computer geeks. At FORTUNE's invitation, they got together one evening in July 1991 to chat in Jobs' Palo Alto home. Their conversation--and this photo--appeared in an issue the following month.