[!todo] Seed note. A starting point, not a finished note yet.
Direct part marking (DPM) applies a barcode or identifier into the material of a part itself, using laser etch, dot peen (a stylus punching a grid of dimples), or chemical etch, rather than printing it on an adhesive label. The point is permanence: the mark survives heat, solvents, abrasion, and paint that would destroy a printed tag, which is why it dominates aerospace, medical devices, and automotive traceability. DPM is where ECC200 earns its error correction, because peened and etched marks have irregular, low-contrast, sometimes non-connected modules that a scanner must read despite the noise. Standards like NASA-STD-6002 and the GS1 direct-marking guidelines exist specifically to keep these marks readable. Seeded from ECC200.