When you create standard RSA keys with ssh-keygen you end up with a private key in PEM format, and a public key in OpenSSH format. Both have been described in detail in my post Public key cryptography: RSA keys.

When you create standard RSA keys with ssh-keygen you end up with a private key in PEM format, and a public key in OpenSSH format. Both have been described in detail in my post Public key cryptography: RSA keys.