Studies tracks the history of all notes, and schedules them for future study. Each day, some of your notes will become due for study. As you study them, they get rescheduled for a later date. Notes you have difficulty with appear more frequently, and the ones you find easy will not be due as often.

Studies actually schedules each combination of facets in a note separately, not just the note as a whole. To give an example, imagine you have a Spanish-English note. You find it easy to remember the Spanish word whenever you see the English word, but you find it difficult to recall the English word given the Spanish word. Studies will schedule the Spanish-to-English combination to appear more often. In this way, you focus on what you have the most difficulty learning.

Studies knows what you are having trouble with because as you study you grade each note. By grading a note while you study, you indicate to Studies whether you knew the note well, i.e. got it right, or didn’t know it. The notes you grade as wrong are scheduled to reappear more often in future so that you learn them better.