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You are viewing a project that is currently in draft state for the Standards Working Group in the Green Software Foundation. This project should not be considered finished or officially supported in any way by the Green Software Foundation or its members.

Terminology and Language Guide

In short: the specification defines the terms it needs to state its requirements (Clause 3). This page explains the extra working terms from the original draft that implementers still meet, and how to read the verbs "shall", "should" and "may".

Terms defined in the specification​

Clause 3 adopts the terms of ISO/IEC 21031:2024, its only normative reference (Clause 2), and adds: web application (3.1), server-side infrastructure (3.2), network transfer (3.3), client-side execution (3.4), end-user device (3.5), third-party service (3.6), energy displacement (3.7), and the component symbols (3.8). Always use the specification's wording for these; this page does not redefine them.

Working terms from the original draft​

These terms appeared in the original draft but are not carried into Clause 3. They are useful shorthand, with the meanings below.

Operational serving​

The runtime operation of a web application serving end-user requests, excluding development, testing and build infrastructure. In the proposed specification this idea is expressed through the boundary and its exclusions (Clause 5.3) rather than as a defined term.

Functional unit (web-specific)​

The unit by which a web application's usage scales, measuring delivered functionality such as user sessions, transactions completed, content items consumed or tasks performed. The parent SCI defines "functional unit"; Clause 6 adds the web-specific expectations. See Choosing a Functional Unit.

Implementation tier​

The level of measurement sophistication an organisation adopts, from entry-level automated measurement to comprehensive instrumentation: Entry, Standard or Advanced. Tiers are guidance only and are always named, never numbered. See Implementation Tiers and Data Quality and Open Question 1.

Reference device​

A representative end-user device used for standardised client-side energy measurement, selected from defined device categories and performance classes. See Reference Devices.

Client-side, server-side and network transfer energy​

The original draft defined these as energy terms (T.2–T.4). The proposed specification defines the underlying infrastructure and activities instead (Clauses 3.2–3.4), which makes the line between components explicit: server-side infrastructure runs up to data-centre facility egress, and network transfer runs from facility egress to the device's network interface. The draft's network term also included content delivery networks; under Clause 5.5, CDN energy measured as facility energy is server-side.

O_dev​

The original draft's abbreviation for development lifecycle operational emissions. It is not a component of SCI for Web: see Development Lifecycle Emissions.

First-party and third-party sub-totals​

O_client_first, O_client_third and the equivalents for O_server and O_network are this site's shorthand for the sub-totals Clause 7.6 requires. "Undifferentiated" marks a component whose sub-totals could not be separated.

Reading "shall", "should" and "may"​

The proposed specification follows ISO drafting rules, which use three verb forms:

Verb formMeaning in ISO drafting
shallA requirement: to conform, you do this
shouldA recommendation: the preferred course, but not a condition of conformance
mayA permission: allowed, not expected

The original draft mixed "MUST" with "SHALL", in the style of internet standards. ISO documents do not use "must" for requirements, so the proposed specification uses "shall" throughout.

These guidelines never use requirement language of their own. Where a page relies on a requirement, it attributes it ("Clause 7.5 requires…"). Everything else on this site is advice: "we recommend", "a common approach is".

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