Verified, not hallucinated.
Most AI study tools make up plausible-sounding questions. Distill only teaches what the textbook actually says, and proves it.
How you study
1Pick a course
Browse textbooks already built into courses. Add one and it shows up under Study.
2Work through a chapter
Each chapter is a path of short units. One opens at a time, so you always know where you are.
3Study concept by concept
Learn the idea, then practice it. Miss a question and it comes back before you move on.
4Come back for reviews
Questions return just before you'd forget them. A few minutes a day is enough.
Why Distill asks you back
Cramming feels productive and fades in days. Distill spaces your reviews so you revisit each idea right as it's slipping: the point where a reminder does the most good. That's the whole engine.
Streaks
A day counts when you finish a unit or clear five reviews. Miss a day and a banked freeze covers you.
Mastery
Each concept fills as your recall strengthens. A book's distilled percentage weights core ideas most.
Hearts
You get 5 hearts. A wrong answer in practice costs one, and one comes back every 30 minutes. Refills can be won, bought with coins, or made unlimited on a paid plan. Reading is never limited.
Why you can trust it
1. Map the book
A model reads each chapter and lays out its concepts and how they depend on each other: the skeleton of the course, in the book's own structure.
2. Write the units
For every concept, it drafts a short explanation and a set of practice questions (multiple choice, fill-in-the-blank, short answer), using only what the chapter actually says.
3. Fact-check every claim
A separate verification pass checks each explanation and answer against the source text. Claims that don't hold up are repaired or removed before you ever see them.
Open the source, always
Every unit card carries a Source button that opens the exact passage it was built from. You never have to take the model's word for it. The receipts are one tap away.
Why not just paste the book into a chatbot?
Because one prompt can't read a whole textbook, and can't show you where an answer came from.
It covers the whole book
The book is mapped chapter by chapter, so every concept gets its own unit. A chatbot works from whatever fits in its context window. Neither of you can tell what it skipped.
Every unit is tied to a passage
Each one is written from the passage it belongs to, then checked back against that same text. The passage stays attached, which is why every card has a Source button. A chatbot answer has nothing to open.
None of this makes a model infallible. It makes its work checkable.
Where the books come from
Every course comes from a public domain or openly licensed textbook: the kind universities publish free for anyone to read, adapt, and share.
Each one names its source and license on the card, the course page, and in the reader. A Distill course is an adaptation of that book, not the book itself.