Katie Keypunch - International model 032 (c.1941)
Here's Elmer's mom, Katie, around 1941. She's running an International model 032 keypunch machine. (The International Business Machines company later became known simply as IBM).
This keypunch was an early model machine; others like it became very common in the 1950's and '60's and were used through the 1970's for data entry. Information was stored by punching a pattern of holes in columns across paper cards. Typing on the keyboard punched the code for that character into the card, and advanced the card one column to the left (like a typewriter) to the next character position.
Here's a picture of a model 032, just like Katie's, in the IBM museum:
Most people called the paper cards simply "IBM Cards", but they were also called "Hollerith Cards", after the person who invented a code used with them. There's actually a picture on the following page of a model 032, very similar to Katie's, bearing the "Hollerith" brand name:
Discarded punch cards were made into Holiday wreaths and other decorations. This same format of punched card was still used into the 21st century in a notorious type of election voting system.
In 1941 when this picture was taken, running these machines was a relatively "high-tech" position that was fun and exciting for Katie, who enjoyed her job at the New York State Corporation Tax Bureau, located in the Alfred Smith State Office Building in Albany, across the street from the Capitol. It was the first office in New York State to implement an automated system for tax billing. One thing Katie did complain about though, was how hot the room got in the summertime.
The mechanical data processing equipment that filled the office gave off a lot of heat, but the building was not yet air conditioned. Other than opening the window, the only relief was a sink with running water. When it was really hot, Katie would go to the sink and run her wrists under the cold water for a few moments to cool off.