You realise are you standing on a metal grid and you can look through to the ground below.

BBC: Imperial War Museum North

This was also a triode: a glass tube containing a heated metal filament which emits electrons, a plate that collects them once they have accelerated through the tube, and a metal grid in between.

ECONOMIST: The middle age of the transistor

Vaporizing nickel onto the surface and removing that screen leaves behind a near-perfect grid of metal, hexagonal dots.

FORBES: Magazine Article

Traditional cameras use either charge-coupled devices (CCDs) or complementary metal oxide semiconductor (CMOS) chips, which capture images on a grid of millions of pixels.

FORBES: Magazine Article