Preferences
Saved in this browser only. No account needed. Clearing your browser data clears it.
Account
Your address, password, connected accounts, plan, sessions, export and deletion.
Nothing on the rest of this page needs an account. None of it is uploaded, except predictions you answered while signed out, which you can add to an account from its dashboard, its review queue page or the Buy Pro form in its settings.
Appearance
Theme and motion apply to this site only, in this browser.
Privacy
Never collected: what you search for, the values you type, the code you write, and anything that identifies you. This build reports nothing at all.
Data
Forgets every step, tick and predict-mode answer this browser remembers. Your theme and motion choices stay.
Reset progress?
Every step, tick and answer this browser remembers is forgotten. There is nothing to restore it from.
This clears what this browser remembers, and nothing leaves it. Progress saved to an account is not touched: only deleting the account removes that, from your account settings. Neither can be undone.
Help
A typo, a wrong step or a broken picture. The Report button in every lesson fills in the details for you.