SSH Key Authentication

SSH key authentication allows you to securely connect from your Linux machine to another Linux machine without typing a password.

Generate SSH key pair:

ssh-keygen

Choose default location.
Do not set a passphrase.

Copy SSH key to the remote machine:

ssh-copy-id username@remote.host

Enter the password for username on the remote machine.

The key is now copied to the remote machine.

Log into the remote machine:

ssh username@remote.host

Original source on DigitalOcean