What are the best guidelines for grammar and punctuation in alerts and user messages?

Question

I know that button titles shouldn't just be "Okay", "Yes" or "No", but be the name of the specific action the button will perform. What about the message itself?

For example, I display this modal alert to the user: " is missing content that it needs to run" with a button that says "Update Content"

Should it be titlecase? Should it have a period at the end? How pithy should the message be? I personally dislike long dialogs, but is this best for the end user?

Answer 1

Let me recommend you to take a look at the book "Language and Communication: Essential Concepts for User Interface and Documentation Design" in case you have some time to deep into the problem at hand.

The following two links are lighter reading. They should be what you are looking for and come with examples. (Although they are from Microsoft, I'm sure you can apply them to other environments.)

• Messages: UI Text Guidelines
• Error Message Guidelines (Windows)

To finish, here is one bonus link also related to errors, entitled "Error Message Guidelines" by Jakob Nielsen, though he doesn't pay much attention to grammar and punctuation.

Answer 2

Messages should be full sentences with correct capitalization, punctuation and grammar.

Mistakes to avoid ...

• Random capitalization of Words in the Middle of sentences.
  Only proper nouns - names of people and places - should be capitalized.
• Incorrect use of apostrophe's.
  Use them to indicate possession (ownership)
• Incorekt speeling.
  If you're not sure, use a dictionary - or draft your message in Word, then copy/paste into your IDE.
• Rambling on and on and on with overly complex and obfuscated language that clouds the point you want to make so that readers have to spend hours (well, minutes) of their time decyphering your words to try and guess the point you might have been trying to get across.
• Being cryptic.
• Using TLA (or FLA) the user might not know.
  Unless it's core to the business, spell out any two-letter-acronyms in full.

Things you should do ...

• Identify the subject of your message.
  Instead of "Do you want to delete this user?"
  Use "Do you want to delete user 'Franklin, B'?"

• Use plain language.
  Instead of "Confirm permanent destruction of the order?"
  Use "Do you want to delete order #23 for the customer 'Franklin, B'?"

For some useful advice on improving your grammar, listen to the Grammar Girl podcast.

Answer 3

Buttons in general should be title case with no punctuation. Messages to the user should be complete sentences, using the proper capitalization and punctuation just like any other sentence. If you don't use complete sentences, to the user it looks like part of the message was lost.

Remember, complete sentences do not need to be long. "Mission accomplished." is a complete sentence. You just need to make sure that you are conveying the complete message to the user and make sure that they understand that they are receiving the complete message.