Physical / electrical concepts

silk_over_copper

DRC warning that silkscreen text overlaps a copper pad. Cosmetic — the soldermask will clip it.

How it looks

Real image: CORE3588, rendered by KiCad from our board file

Bottom side of CORE3588 near the logo. The ink stays clear of every pad, so there is no warning here.

1Silkscreen: the white printed ink of the logo on the back of CORE3588. It may cross tracks, because they are hidden under the soldermask.
2A pad of the 2-pin header H2: bare metal, no soldermask. If silkscreen ink landed on it, DRC would warn silk_over_copper.

A cosmetic warning, unlike shorting_items or unconnected_items, which are critical errors.

It involves the printing layers (silkscreen, soldermask), not the copper the router lays.