What is plain language?

A communication is in plain language if its wording, structure, and design are so clear that the intended readers can easily find what they need, understand what they find, and use that information

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An approach, an attitude

Writing in plain language requires you to adopt a particular approach, or attitude, to writing. You need to be mainly focused on what the reader needs to do or to know. On what works for the reader.

You need to be less focused on what you want to say, on how you want to be seen, or on how you want to sound.

There may be content that your reader won’t be interested in but that you need to include (for example, for compliance reasons). In such cases, that content should rarely be your focus.

Thankfully, an internationally agreed definition of plain language helps us think through what we need to do, and to aim for, when we set out to write in plain language.

A definition of plain language

The journey to the definition

The definition of plain language evolved through a multi-year process led by the International Plain Language Federation and its 3 founding bodies: the Center for Plain Language, Clarity, and PLAIN.

The need for a definition was discussed in 2008 at a conference in Mexico City. Possible approaches to the definition were outlined in an options paper published in 2010. Drafts of the definition were reviewed in plenary sessions at international conferences in Stockholm, Vancouver, and Washington, D.C.

The definition is available in multiple languages

Then in 2014, at a conference in Antwerp, the Federation and its 3 founding bodies formally adopted this definition:

A communication is in plain language if its wording, structure, and design are so clear that the intended readers can easily find what they need, understand what they find, and use that information.

The definition has stood the test of time. Indeed, it forms the basis of the plain language standard published by the International Organization for Standardization (ISO). The definition has been translated into multiple languages.

ISO’s standard and the definition

ISO published Part 1 of its plain language standard in 2023. It covers general principles and guidelines. It works in most, if not all, languages and across all sectors.

Part 1 of the standard, and the parts that are following after, are built on the Federation’s definition.

You can read the Federation’s resources about the standard.

What is involved in writing plain language 

This will give you a brief introduction to what’s involved in writing plain language and how it relates to the definition. The ISO plain language standard provides many more details on methods and techniques you can use to write plain language documents.

The definition’s 4 principles to focus on 

The definition has 4 principles that writers need to focus on. ISO’s standard is built around these 4 principles.

Here’s the definition again, with the 4 principles in bold:

A communication is in plain language if its wording, structure, and design are so clear that the intended readers can easily find what they need, understand what they find, and use that information.

To write a plain language document you need to make sure your document has these features:

    • The document has all the information the reader needs. And very little information they don’t need.
    • The document is set up so that readers find the information they need. The way to do that is through document structure and document design.
    • The document is written in a way that readers can understand, in familiar words.

The principles find, need, and understand work together so that the reader can use the information to do what the document was intended for. For example, if the document is telling them what they need to do or answering questions they had.

The definition’s 3 methods to use 

The standard also provides 3 methods you can use to achieve the definition’s principles.

Here’s the definition again, this time with the 3 methods in bold:

A communication is in plain language if its wording, structure, and design are so clear that the intended readers can easily find what they need, understand what they find, and use that information.

In many ways, the phrase “plain language” is inaccurate. It places too much emphasis on language: on words and on sentences. The ISO plain language standard has roughly 485 ideas. These cover a variety of language issues (such as the content’s structure, findability, understandability, and usability) but only 7% of these ideas focus on word choice. The standard focuses on effective combinations of wording, structure and design to support readers.

1.    Wording

Using clear words and sentences is an important part of writing in plain language. Here are some examples of how you can choose the right words and sentence structure.

    • Use words that are familiar to the intended audience. A plain language document can use any word if the document’s readers will understand the word. Indeed, if you use a word your readers won’t understand, then (as the phrase goes) you might as well put the word in a dingbat font. Or, rather, you might as well put the word in Á♣§¥⊗ζℜ.
    • Avoid abbreviations where you can. If you must use them, try to use a shortened form rather than an acronym or initialism (for example, for the International Plain Language Federation, we often refer to the Federation instead of the IPLF).
    • Use clear sentence structures. Aim for one idea per sentence.
    • Address your readers directly when you can.

 2.    Structure

A document’s structure should help readers to find they information they need. These are a few examples of good document structure.

    • Put the ideas in the document in a logical order, according to the reader’s logic (not the writer’s logic).
    • Put the most important information first.
    • Put information that most readers will need before information that only some of the readers will need.

3.    Design

The design of a document makes the structure visible and makes it efficient and comfortable to read. Here are a few examples of how you can do that.

    • Group information under useful and accurate headings that reflect how the reader sees the content (not how the writer sees it). Separate groups by using white space.
    • Make important information visually prominent so that it draws the reader’s attention.
    • Provide a visual sequence to guide readers through a document.
    • Apply visual design uniformly throughout a document.

The ISO plain language standard has many more methods you can use to achieve the definition’s 4 principles. The ones listed here are just a few examples.

Learning from readers 

The only way to be sure a document is working for its readers is to ask them. You can ask them by testing (evaluating) the document with a sample of its readers. Doing this is constantly educative. You learn from readers about how to improve your document.

Fields that are related to plain language

There are several fields that relate to plain language even though they aren’t the same as plain language. These are some examples:

    • literacy in all its areas: health literacy, visual literacy, digital literacy
    • user experience design, usability
    • accessibility

This will give you a brief introduction to what’s involved in writing plain language and how it relates to the definition. The ISO plain language standard provides many more details on methods and techniques you can use to write plain language documents.

Accessibility and plain language

Plain language and accessibility are different, but they are beginning to merge.  

Communication fields that appear similar to plain language

There are several approaches to clear communication that can appear to be the same as plain language. These approaches are useful in the areas they are meant to serve and we see their value. But they aren’t the same as plain language. It’s important to know the differences and to not confuse them with plain language.

It’s also important to note that plain language is not a language variant, variety, or register.

Easy English

Easy English is meant for people with learning or cognitive disabilities, or those who have limited English (such as people with low literacy skills or who are English language learners).

Controlled languages

Controlled languages are language standards with restricted vocabulary and grammar. They are used primarily for two purposes: to improve clarity for human readers and to improve the ability of computers to process language. Controlled languages can be developed based on any natural language.

Here are 2 examples:

 Simplified Technical English

      • Simplified Technical English is used in industry to prepare technical manuals that will be used by second-language speakers of English.
      • Its original use was in the aerospace industry. Because of its success there, it’s now used by many other industries.
      • It helps English second-language speakers to unambiguously understand technical manuals written in English. It applies only to English.

Ogden’s Basic English

      • In the 1920s, a linguist named Charles Ogden developed a simplified form of English to be an international second language. It used only 850 key words. He called it Basic English.