Stitch/pattern name?

I know there’s a way to knit something in such a manner that you can “cross-stitch” (not the right term, but I think you know what I’m trying to say) a design on when pattern is ccomplete. But what is that stitch/pattern called? I want to make my hubby a hat and then add the IH International Harvester design on it.

Do you mean duplicate stitch?

Embroidery: How to do the Duplicate Stitch

The video that GG linked to shows duplicate stitch on top of stockinette stitch. You can also do duplicate stitch on garter stitch but it’s easier on stockinette (knit one row, purl one row when you knit flat or knit all stitches in the round).

That’s exactly what I was after! Thanks a bunch.