Passwordless SSH Login

On the host create the private and the public key:
ssh-keygen
Just hit enter to keep the default values.
Usually, I only needs this for some uncritical test- and development-setups where security does not matter that much.
There will be two files in ~/ssh.
One is private key id_rsa and id_rsa is the public key.
Now copy the public key to the server with:
ssh-copy-id [email protected]
Check if it is possible to log into the server without having to provide the password:
Yes, it is really that simple.