A: This depends on if you want symmetric or asymmetric encryption. For symmetic encryption, you can use the following… To encrypt: > openssl aes-256-cbc -salt -a -e -in plaintext.txt -out encrypted.txt   To decrypt this, you can use the following. > openssl aes-256-cbc -salt -a -d -in encrypted.txt -out plaintext.txt   Now, for Asymmetric encryption [...]