Pocket protector

Pocket protectors were originally made of polyvinyl chloride (PVC).

The pocket protector was invented during World War II by Hurley Smith while he was working in Buffalo, New York.

[1] A competing claim for the invention came from Long Island plastics magnate Gerson Strassberg around 1952.

A more general market soon arose, made up of students, engineers, and white-collar workers in a variety of fields.

They have become part of a "nerd" or "geek" fashion stereotype, probably because of their association with engineers or students.