What Does SSH Mean, and Why Does Key-Based Login Matter?

Connecting over SSH opens an encrypted channel between your computer and the server, then drops you into a command-line session running on that server directly. From there, commands you type — listing files, editing a config, running a script — execute exactly as if you were sitting at the machine itself, rather than going through a web interface that translates clicks into actions behind the scenes.

That encryption covers the entire session, not just the login. Every keystroke, every line of output, every file transferred over SSH's companion protocols travels encrypted, which is why it remains the standard way to manage a server remotely without exposing what you're doing to anyone intercepting the connection.

SSH supports two ways to log in: a password, or a cryptographic key pair, where a private key stays on your computer and a matching public key sits on the server. Key-based login is considered safer because it isn't vulnerable to the guessing and brute-force attacks that target password logins constantly, and it isn't something that can be reused if it leaks from an unrelated data breach the way a reused password can be.

Setting up key-based access takes a few extra minutes the first time — generating a key pair and adding the public half to the server — but after that, logging in doesn't require typing a password at all, which is both more convenient and considerably harder to compromise remotely.