Everything you need to get the most out of Underlayer.
Click Register in the top navigation to create a free account. You can also browse courses without an account, but progress won't be saved.
Visit the Courses page to see available courses. Each course is structured into modules and concepts, progressing from fundamentals to advanced topics.
Click any concept in a course to begin learning. Each lesson includes an explanation, examples, and practice exercises. Work through them at your own pace.
The Dashboard gives you a quick overview: due reviews, learning streak, knowledge health, and recommended next steps.
Underlayer is built around active recall — the practice of retrieving information from memory. After each lesson, exercises test what you just learned. This is harder than re-reading, but far more effective.
The FSRS algorithm schedules reviews just before you forget. This means you review concepts at the optimal time: not too early (wasted effort) and not too late (forgotten). Trust the system — it adapts to you.
If a concept feels hard, that's by design. Difficulty is how learning happens. The platform tracks your struggles and provides targeted review to strengthen weak areas.
Even 10 minutes of daily review maintains knowledge. The Dashboard shows your due items. Consistency matters more than marathon sessions.
Click Review in the navigation, or use the "Start Review" button on the Dashboard. You'll see concepts that are due for review.
After each review item, rate how well you remembered:
Underlayer offers multiple review modes: Quick Review, Deep Review, Weakness Focus, and more. Choose based on your available time and learning goals.
Review your past sessions to see how your recall has improved over time. Visit the Progress page for detailed analytics.
Your Knowledge Health score reflects how well you've retained concepts. It considers review accuracy, time since last review, and difficulty ratings. A healthy score means your knowledge is stable.
Each concept progresses through mastery levels: New → Learning → Review → Mastered. The FSRS algorithm determines when you've truly mastered a concept based on your performance.
The platform automatically identifies concepts you struggle with and groups them by category. Visit the Weakness Dashboard to see targeted repair suggestions.
You can export your progress, review history, and analytics as JSON from the Settings page. Your data belongs to you.
Underlayer supports keyboard shortcuts for faster navigation. View all shortcuts →