What is the public key?

It is the key that can be shared and can be used to encrypt the message.

openssl genrsa -out my privatekey.pem 2068

![]

What is the private key?

It is the key known only to the owner and can be used to decrypt the message

openssl rsa -pubout -in myprivatekey.pem -out my publickey.pem

What can this key pair be used for?

These keys are used to secure the information or message and authenticate the message. Public key can be used to encrypt the message and private key can decrypt the message

Why must the private key be protected?

To secure the information from spy and unrelated person.