RSA Tool
For my Introductory Computer Science course's final project, I chose to build a RSA tool from scratch using Python. It encrypts and decrypts alphanumeric strings by using their ASCII values, and has a password manager feature where users can store their passwords. The users can even load in their own public and private keys to work with messages encrypted in a different instance of the program. This project was a great learning experience, as it was my first real look at cryptography. I implemented complex modular arithmetic, such as the Extended Euclidean Algorithm.
It's very basic, but helped me understand the math behind RSA a lot better and was fun to make!