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Headlines & Titles

Content written for HELIO HMIs, the HELIO IDE, and the HELIO Docs uses title case for headlines and titles to make them stand out clearly from the body text.

HELIO makes use of the rules of the Chicago Manual of Style to apply a consistent title case.

Why?​

»Build language patterns. Consistency builds familiarity, helping your app feel cohesive, intuitive, and thoughtfully designed. It also makes writing for your app easier, as you can return to these patterns again and again.«

»…how you format your text is a reflection of your app’s voice. Title case is more formal, while sentence case is more casual. Choose a style that fits your app.«

Apple’s Human Interface Guidelines > Writing

Guidelines​

Do

  1. Capitalize with confidence: make use of automated tools to quickly apply these rules automatically, such as:

  2. 2. When in doubt, refer to Relevant Rules of the Chicago Manual of Style below.

Don't!

  • Apply title case manually – just don't!

Relevant Rules of the Chicago Manual of Style​

»The conventions of title case are governed mainly by emphasis and grammar. The following rules, though occasionally arbitrary, are intended primarily to facilitate the consistent styling of titles mentioned or cited in text and notes. Note that Chicago now recommends capitalizing prepositions of five letters or more (see rule 3).«

Source: The Chicago Manual of Style: Principles of title case

  1. Capitalize the first and last words in titles and subtitles (but see rule 7) and all other major words (nouns, pronouns, verbs, adjectives, adverbs, and some conjunctions—but see rule 4).
  2. Lowercase the articles the, a, and an.
  3. Lowercase prepositions of fewer than five letters, except when they are used adverbially or adjectivally (up in Look Up, down in Turn Down, on in The On Button, to in Come To, etc.) or when they compose part of a Latin expression used adjectivally or adverbially (De Facto, In Vitro, etc.). In rare cases, a shorter preposition may be capitalized when paired with a longer preposition (for in For and Against). Note that the five-letter rule includes abbreviations (e.g., Versus would be capitalized, but vs. would not be).
  4. Lowercase the common coordinating conjunctions and, but, for, or, and nor.
  5. Lowercase to not only as a preposition (rule 3) but also as part of an infinitive (to Run, to Hide, etc.) and lowercase as in any grammatical function.

No one should ever have to come this far!

  1. Lowercase the part of a proper name that would be lowercased in text, such as de or von.
  2. Lowercase the second part of a species name, such as fulvescens in Acipenser fulvescens, even if it is the last word in a title or subtitle.