Style Guide

This page provides content guidelines for the Istio documentation. These are guidelines, not rules, so use your best judgment, and feel free to propose changes to this document in a pull request.

Formatting standards

Use consistent capitalization

Don't split configuration type names into separate words and follow the original capitalization. For example, use IstioRoleBinding, not Istio Role Binding or istio role binding.

Use angle brackets for placeholders

Use angle brackets for placeholders. Tell the reader what a placeholder represents.

1. Display information about a pod:

   $ kubectl describe pod <pod-name>

   where <pod-name> is the name of one of your pods.

Use bold for user interface elements

Use italics to define or introduce new terms

Use code style for filenames, directories, and paths

Use code style for inline code and commands

Use code style for object field names

Use title capitalization for title: front-matter

The text for the title: front-matter should use full title capitalization (first letter of every word). This is unlike headings within the document, as described below.

Only capitalize the first letter of headings

For any headings, only apply an uppercase letter to the first word of the heading, except if a word is a proper noun or an acronym. Note that the title: annotation in markdown uses full capitalization.

Terminology standards

Some standard terms we want to use consistently within the documentation for clarity.

Envoy

We prefer to use “Envoy” as it’s a more concrete term than “proxy” and will resonate if used consistently throughout the docs.

Synonyms:

• “Envoy sidecar” - ok
• “Envoy proxy” - ok
• “The Istio proxy” – best to avoid unless you’re talking about advanced scenarios where another proxy might be used.
• “Sidecar” – mostly restricted to conceptual docs
• “Proxy” – only if context is obvious

Related Terms:

• Proxy agent - This is a minor infrastructural component and should only show up in low-level detail documentation. It is not a proper noun.

Miscellaneous

Best practices

Use present tense

Exception: Use future or past tense if it is required to convey the correct meaning.

Use active voice

Exception: Use passive voice if active voice leads to an awkward construction.

Use simple and direct language

Use simple and direct language. Avoid using unnecessary phrases, such as saying “please.”

Address the reader as “you”

Create useful links

There are good hyperlinks, and bad hyperlinks. The common practice of calling links here or click here are examples of bad hyperlinks. Check out this excellent article explaining what makes a good hyperlink and try to keep these guidelines in mind when creating or reviewing site content.

Why “click here” is a terrible link, and what to write instead.

Avoid using “we”

Using “we” in a sentence can be confusing, because the reader might not know whether they're part of the “we” you're describing.

Avoid jargon and idioms

Some readers speak English as a second language. Avoid jargon and idioms to help make their understanding easier.

Avoid statements about the future

Avoid making promises or giving hints about the future. If you need to talk about an alpha feature, put the text under a heading that identifies it as alpha information.

Avoid statements that will soon be out of date

Avoid words like “currently” and “new”. A feature that is new today might not be considered new in a few months.

See also