RSA Experimenter vs Probability for Computing

This app is intended as a tool for understanding a method of encrypting messages known as Public Key Cryptography (RSA). Invented in the 1970's this method still (in 2023) underlies much of the secure electronic transfer of information including communication with a bank (either online or from ATM machines), ordering goods online, transfering medical records and much more. The app is NOT designed for actually sending secure messages; the version of the method implemented here is intensionally a 'toy' version which is more easily understood than the full version. You will see how messages are encoded and decoded and their authenticity verified by using the app to exchange messages with colleagues and friends. The extensive help pages explain most of the mathematics behind this method. It involves concepts often presented to 2nd or 3rd year university students but is accessible to smart and curious middle-school students; the original version of this app was in fact written to accompany a series of sessions of the author with the seventh-grade math class of one of his grandchildren.

Probability for Computing is an independent study app for learners who want focused practice in probability concepts used in computing, data, algorithms, systems, and technical interviews. Work through 160 questions across Fundamentals, Practical Skills, Common Pitfalls, and Advanced Concepts. Each question includes an explanation so you can understand the reasoning, not just memorize an answer. Features: - FSRS spaced-repetition intervals for long-term review - Weak-point heatmap to spot topics that need work - Daily challenge for steady practice - Mock exams for timed review - Offline practice for commutes, classrooms, and travel - No login required Use it as a companion for coursework, self-study, interview prep, or exam-style review when you need short, repeatable probability drills. Independent study app for Probability for Computing practice. Not affiliated with, endorsed by, or sponsored by any company, certification body, exam operator, or vendor. All trademarks belong to their respective owners. Practice offline, no login required.