SuperMemo

Content sourced from Wikipedia, licensed under CC BY-SA 3.0.

SuperMemo is a learning method and software created in Poland by Piotr Woźniak and SuperMemo World, starting in 1985. It uses spaced repetition to help long-term memory, deciding when you should review each item.

How it works:
- You build a database of questions and answers.
- During reviews you rate how well you recalled the answer on a scale from 0 to 5. The program uses this rating to schedule future reviews, so harder items show up more often.
- It supports text, images, video, and HTML in questions and answers.

Incremental Reading:
- A unique feature that lets you import long texts, read them inside SuperMemo, bookmark where you left off, extract important bits, and turn those extracts into questions to study. It also prioritizes the most important information when you can’t review everything.

Algorithms:
- The software has evolved through several algorithms: SM-0 (the original), SM-2 (the first computer-based version used in early releases), and later SM-5, SM-8, SM-11, SM-15, SM-17, and the latest SM-18 (2019).
- The SM-2 approach influenced many other apps, and some programs like Anki and Mnemosyne use variants of it. Org-drill uses SM-5 by default.

Availability:
- Desktop and mobile options for Windows, Windows CE, Windows Mobile, Palm OS, and more. Some course software can run in a web browser or offline.

Current version:
- Stable release 19.1 (April 23, 2025). Size about 12.5 MB. Proprietary software.