A specification is a detailed description that explains exactly what something should be like or how it should be made. When engineers design a new bicycle, they write specifications that might include the frame's exact measurements, the type of metal to use, how much weight it must support, and what color it should be painted. These precise details ensure that everyone building the bicycle knows exactly what to create.

Specifications matter because they turn vague ideas into clear instructions. If you asked a builder to “make a treehouse,” they'd have countless questions: How high? How big? What materials? But if you provided specifications showing it should be eight feet off the ground, six feet wide, built from treated lumber, and include a rope ladder, they'd know precisely what to build.

The word often gets shortened to “specs” in casual conversation. A computer's specs might list its processor speed, memory size, and storage capacity. When something is built “to spec,” it means it matches the specifications exactly. Sometimes people say a product “meets specifications” to confirm it's what was ordered.

In school, a teacher might give you specifications for a project, detailing the required length, format, and topics to cover. Following those specifications carefully shows you understand not just what to do, but exactly how to do it right.