A sherd is made of ceramic, while a shard is made of glass or metal.

This paragraph in the introduction of Marianne Bellotti’s book Kill it with Fire caught my eye (emphasis mine):

I never became the swashbuckling international aid worker I imagined myself to be, but I ended up finding my applied anthropology work applied in legacy modernizations. Like pottery sherds, old computer programs are artifacts of human thought. There’s so much you can tell about an organization’s past by looking at its code.

I’d never heard the term “sherd” before – apparently it’s a word used by archeologists and historians to describe fragments of ceramic. It’s a shortening of the word “potsherd”. Although colloquial English would describe those as “shards”, specialists use that word to refer to fragments of glass or metal.

It’s not a word I expect to use, but it was a cool sidequest while reading about digital archeology.