How did punch cards primarily store data?

Punch cards primarily stored data through the holes that were physically punched into the card. Each hole's presence or absence represented a different piece of information, such as a particular character or command. This binary method of data representation allowed machines, like early computers and sorting machines, to read the information by detecting the patterns of holes. The coding system gave a structured way to input and process data, making punch cards an essential technology for data entry and processing in the early days of computing.