Protocol (computing)
Etymology
From Greek "protokollon" — "protos" (first) plus "kolla" (glue) — the first sheet glued to a manuscript that recorded its contents and authenticity. It passed into diplomacy as the rules of formal conduct between states, then into computing for the rules governing how machines communicate. The thread throughout is a fixed, agreed formality that everyone honors.
noun · /PROH-tuh-kawl/
An agreed set of rules that lets two systems exchange information in a way both understand.
What it names
The shared etiquette that lets devices built by strangers, decades apart, still talk — the reason any browser can open any website.
Example
The "s" in https signals a secure protocol, so the connection is encrypted.
Related idea
A protocol is not the same as a format: a format describes how a single file is structured, while a protocol governs the back-and-forth conversation between two parties.
noun · /PROH-tuh-kawl/
The system of accepted rules governing correct conduct, ceremony, and precedence in official or diplomatic settings.
What it names
The invisible choreography of formal life — who is greeted first, where dignitaries sit — a code of manners, not a technical spec.
Example
Seating heads of state at the summit required strict attention to diplomatic protocol.
Related idea
Close to etiquette but grander and more codified — protocol governs precedence and ceremony at the level of states, deciding who is greeted first and where dignitaries sit.
noun · /PROH-tuh-kawl/
A fixed, official procedure for carrying out a task, treatment, or experiment.
What it names
A step-by-step recipe that must be followed exactly to keep results safe, valid, or comparable — as in a medical or research protocol.
Example
The trial followed a strict protocol for dosing and monitoring each patient.
Related idea
Where the etiquette sense governs how people behave, this sense governs how a task is done — a documented method carried out by people, close in spirit to an algorithm.