Ephemera

Etymology

From Greek "ephemeros," lasting only a day (epi, for + hemera, day); an "ephemeron" was a mayfly, an insect living but a day. The plural came to name things built to be discarded.

noun · /ih-FEM-er-uh/
Transient printed or everyday items — tickets, flyers, postcards — not meant to last but now collected.
What it names
The disposable material culture of daily life, valuable precisely because it was made to be thrown away.
Example
The archive’s most revealing box held ephemera — a wartime ration card, a dance ticket, a shopping list.
Related idea
The noun beside the adjective ephemeral; ephemera is the physical debris of the fleeting, saved precisely because it was designed to vanish.