By giving writers rules, whether they are about how to use punctuation or how to present your brand or agency, a style guide helps your users understand what you are trying to say. By promoting consistency, you avoid making users reinterpret your words over and over.
Some style guidelines are arbitrary, while others reflect proven best practices. Either way, they help an organization produce consistently effective content. We provide guidelines that reflect best practices as we know them here at 18F. Writing for other audiences might require different rules, but we hope our suggestions can be a good starting point for your organization.