Product Development Glossary: Plain Definitions

Terms are listed alphabetically. Where a term has a page of its own on this site, it is linked.

Analysis: Verifying a requirement by calculation or simulation rather than by testing a physical part. One of the five verification methods.
Assembly: Putting parts together into a finished product. Also the name for the group of parts that result. The cost and difficulty of assembly is designed, not accidental; see DFA.
BOM (bill of materials): The list of every part in a product, with quantities and, usually, costs and suppliers. The BOM is the backbone of the unit cost.
CAD (computer-aided design): The 3D computer model of a part or product. Manufacturers make parts from CAD files and the drawings produced from them. Owning the CAD is a large part of owning the design.
Certification: Formal testing by an accredited lab showing that a product meets a safety, electromagnetic, radio, or other regulatory standard. Required to sell many products legally, and routinely missing from first budgets.
Contract manufacturer (CM): A company that makes products designed by someone else. Some also offer engineering services; many expect to receive a finished, production-ready design.
Deliverable: A specific thing received at the end of a piece of work: a report, a set of files, a unit. A quote should name its deliverables.
Design review: A structured meeting in which a design is examined against its requirements before it moves forward. One of the five verification methods.
DFA (design for assembly): Shaping a design so that it can be put together quickly, consistently and with few mistakes: fewer parts, fewer orientations, fewer tools.
DFM (design for manufacturing): Shaping a design so that it can be made efficiently by the intended production process. A molded part designed with DFM has uniform walls, draft angles and no undercuts. Most of this work happens in Preproduction.
Discovery: The structured conversation and research at the start of a project that produces the first requirements document. The main activity of Project Initiation.
Draft angle: A slight taper on the walls of a molded or cast part so it can be removed from the mold. A detail that prototype parts do not need and production parts must have.
Exit criteria: The conditions that must be true before a phase is considered complete and the next phase makes sense. Defined at the start of the phase, checked at the gate.
Feasibility: The phase that checks whether an idea can work at all, on paper, before anything is built. See Phase 2.
Firmware: Software that runs on the small computer inside an electronic product. Written by a firmware engineer, usually during the Prototype phase, and owned under the same terms as the rest of the design.
Fixed price: One agreed price for a defined deliverable. The firm carries the risk of the work taking longer. Fits known scope. See Costs.
FRS (functional requirements specification): A written list of what a product must do, in verifiable statements, without saying how. Also called a PRD or simply a requirements document. The single most useful document in development; see Project Initiation.
Industrial design: The discipline concerned with a product's form, appearance, feel and usability. Distinct from engineering, which is concerned with making it work and making it manufacturable.
Inspection: Verifying a requirement by examining or measuring a part. One of the five verification methods.
IP (intellectual property): The ownable result of creative and technical work: the design, CAD files, drawings, firmware, test methods, and any inventions. Who owns the IP created during development must be settled in writing before work starts.
Landed cost: The full cost of a unit delivered to the owner's warehouse: the manufacturing cost plus freight, duties, insurance and handling. The number that matters for pricing.
Lead time: The time between placing an order and receiving it. Tooling lead times and certification lab schedules often set the pace of Preproduction.
Looks-like prototype: An appearance model with no working internals. Used for photography, user reaction and packaging design. See Prototype.
MOQ (minimum order quantity): The smallest quantity a supplier will accept for an order. Often sets the size of the first production run whether the owner wants it to or not.
NDA (non-disclosure agreement): A contract in which parties agree not to share each other's confidential information. A mutual NDA binds both sides. An NDA protects information; it does not transfer ownership of anything and does not oblige anyone to do business.
Phase: A stage of development that exists to answer one question. This site uses six: Project Initiation, Feasibility, Proof of Concept, Prototype, Preproduction and Production. See The process.
Phase gate: The decision point at the end of a phase: go on, change direction, pause, or stop, based on what the phase found.
Pilot run: A small production batch made with the real tooling and process, to find the problems that only appear when real parts from real suppliers meet on a real assembly line.
Proof of concept: A rough build of only the risky part of a product, to prove it works in real hardware. Not a prototype. See Phase 3.
Prototype: One or a few units of the complete product, built to work and (usually) look like the final product. See Phase 4.
Requirement: A single statement of something the product must do. Good requirements are specific, unique, unambiguous, positive and verifiable.
Shall / should: In a requirements document, "shall" means mandatory and "should" means preferred. Every "shall" is a cost lever.
Similarity: Verifying a requirement by showing the design is close enough to a product already known to meet it. One of the five verification methods.
Sustaining engineering: Ongoing engineering on a product already in production: field fixes, obsolete-part replacement, cost reduction. See Production.
T&M (time and materials): Billing by the hour plus parts, against an estimate. The owner carries the risk of the work taking longer, and keeps the saving if it takes less. Fits uncertain work.
Test: Verifying a requirement by operating the product or a part of it and measuring the result. One of the five verification methods, and the most expensive.
Tolerance: The allowed variation in a dimension. Tight tolerances cost more. Setting them well is a large part of design for manufacturing.
Tooling: The molds, dies, jigs and fixtures used to make parts in production. A large one-time cost, a long lead time, and the point at which a design becomes expensive to change.
Unit cost: What one unit costs to make. Has two very different values: the prototype unit cost (now, one at a time, no tooling) and the production unit cost (at volume, with tooling). See Costs.
Verification: Showing that a product meets a requirement, by analysis, design review, inspection, similarity or test. Every verifiable requirement names which.
Works-like prototype: A prototype that functions correctly but looks rough. A step above a proof of concept.
Yield: The share of units made that pass inspection. A yield of 95% means one in twenty is scrapped or reworked, and that cost is spread over the good ones.

Missing a term? Send it to j.wayne.weber@pm.me and it will likely be added.