Non-normative

Non-normative refers to content that is not considered part of the official standard, specification, or recommendation. It represents additional information or examples that supplement and clarify the normative content. While the normative content is required for interoperability and conformance, non-normative content aims to provide additional guidance, explanation, or clarification to aid in understanding and implementation.

Purpose

The purpose of non-normative content is to provide additional information to help developers understand and implement the normative content. Normative content is the core of a specification, standard, or recommendation and defines what is required for interoperability and conformance. Non-normative content is not required for conformance, but it can be helpful to developers, implementers, and users.

Non-normative content can take various forms, including informative text, examples, diagrams, tutorials, and test cases. It can provide additional context, rationale, or best practices. It can also address common questions or issues that arise during implementation or testing. Non-normative content can help reduce ambiguity, increase clarity, and facilitate adoption of the normative content.

Usage

Non-normative content is typically found in the appendix or annex of a specification, standard, or recommendation. It is clearly labeled as non-normative to distinguish it from the normative content. For example, in the HTML5 specification, the “References” section is non-normative and provides additional resources for developers. Similarly, in the CSS2.1 specification, the “Examples” section is non-normative and demonstrates various usage scenarios.

Non-normative content is not binding and may be subject to change or removal without affecting the normative content. However, non-normative content is still part of the specification, standard, or recommendation and should be treated with care. It may contain errors, omissions, or inconsistencies, and should be used with caution.

Non-normative content can be particularly useful for implementers who need to understand the normative content in depth and apply it to specific contexts. Non-normative content can provide practical guidance and examples that illustrate how the normative content can be used in real-world scenarios. However, implementers should not rely solely on non-normative content and should always refer to the normative content for authoritative information.

Non-normative content can also be helpful for users who want to learn more about the specification, standard, or recommendation. Non-normative content can provide explanations, use cases, and best practices that help users understand how the technology works and how to use it effectively. However, users should be aware that non-normative content is not part of the official standard and may not be up-to-date or accurate.

Examples

Here are some examples of non-normative content in popular Web-related specifications:

• The “Introduction” section of the HTTP/1.1 specification provides a non-normative overview of the protocol and its features.
• The “Examples” section of the CSS Grid Layout specification demonstrates various layout scenarios using the Grid Layout module.
• The “Notes” and “Examples” sections of the HTML5 specification provide additional information and usage examples for various elements and attributes.
• The “Test Cases” section of the WAI-ARIA Authoring Practices provides non-normative examples of how to create accessible web content using ARIA.
• The “Implementation Notes” section of the ECMAScript Language Specification provides guidance and recommendations for implementers of the JavaScript language.