According to Wikipedia, a Vigenère Cipher is a method of encrypting using multiple Ceasar Ciphers. To encrypt a message with this project, enter a key phrase (this controls how many places each letter is offset, if you know how a Ceasar cipher works). This phrase should be relatively short. Then, enter the message that you want to keep safe (only eligible characters right now are the alphabet and spaces). When it is encrypted, you can copypaste. Good luck deciphering an encrypted message without the key phrase!
Decipherer: https://scratch.mit.edu/projects/303622640/ Thanks to my CSP class for teaching me what a Vigenère Cipher is and how they work.