Forum terminology guide for new members

Jumping into discussions here is confusing if you do not know what certain terms refer to. Here is a plain-language rundown of the most commonly used terms.

• OVD — Optically Variable Device. The holographic overlay on an ID card that shifts colors and patterns when you tilt it. Higher-end OVDs are harder to replicate than simple foil stamps.
• AAMVA — American Association of Motor Vehicle Administrators. They publish the technical standard that defines what data goes into the PDF417 barcode on US driver's licenses. When someone says a barcode is "AAMVA compliant," they mean it follows this standard.
• PDF417 — The 2D barcode format used on the back of US driver's licenses. The rectangular barcode with stacked rows of black and white patterns. Not the same as a QR code.
• OVI — Optically Variable Ink. A security ink that appears different colors at different viewing angles, similar to the gold-to-green shift on US currency. Harder to produce than standard holographic overlays.
• Ghost image — The small, faded secondary photo of the cardholder that appears on many state licenses. Usually positioned away from the main photo.
• Polycarbonate / poly / PC — The rigid plastic material used in higher-quality ID cards. More durable than PVC and laser-engravable. When vendors say "polycarbonate construction" it should mean the card is made of PC layers bonded together.
• PVC — Polyvinyl chloride. The plastic used in credit cards. Cheaper than polycarbonate, less durable, and cannot be laser-engraved in the same way. A PVC card pretending to be polycarbonate is lighter and slightly more flexible.
• Reship / reship policy — The vendor's offer to send a replacement at no charge if the original is lost in transit. Most vendors have a specific timeline before this applies (typically 30 days).
• Proof — The digital mockup of your card that vendors send for approval before printing. Review it carefully before approving.

There are more terms, but these are the ones that appear in almost every quality discussion thread. Knowing them makes the rest of the discussion make sense.