Voice

Plain English, encouraging, practical. Explain why, not just what. Second person for instruction (“You’ll learn to…”), third person for the product. Sentence case everywhere — except uppercase mono kickers and lesson-type badges. No emoji in product copy.

Buttons — name the action, not the mechanism

DoStart learning · Send sign-in link · Browse courses

Don’tSubmit · Click here · OK

Errors — what happened, and what to do

DoWe could not find an account for that address. Create one instead.

Don’tError: authentication failed (code 401)

Never blame the reader (“you entered an invalid…”). Never expose a status code as the whole message.

Empty states — three required parts

Do No courses yet
Courses you start will appear here so you can pick up where you left off.
Browse courses →

Don’tNo data.

What is not here · why · the one thing to do. If there genuinely is nothing to do, say so — do not leave the reader to guess.

Labels & kickers

Mono, uppercase, tracked — and always a noun: DURATION, LEVEL, LESSON 03. Section kickers keep the code-comment voice: // Getting started.

Numbers

Concrete only — “75%+ coverage”, “200-record data load”, “five sections”. Never decorative stats. Mono and tabular so digits line up in a column.