I've reading about asymmetric cryptography and I know that the concept is to keep the private key to yourself and distribute the public key. But recently I accessed a remote server using SSH with a .pem file. The command I used to access was
ssh -i ./key/private_key.pem -l comp <ip_address>
I checked the manual page for ssh and it says
Selects a file from which the identity (private key) for public key authentication is read.
I wonder why I was given a file with private key, how was I authenticated, and what did the server have?