How is a key different from a password?

Question

SSH

In one article on SSH security, I came across this text:

If you are still using SSH access with a password, change your habit immediately. This is dangerous. It is better to use access by key.

I looked at the contents of my private key - there are several lines, a total of about 1000 characters. And if you use a password of 1000 characters? Does the level of security compare?

Answer 1

Does the level of security compare?

No, never.
The key is a one-time generated on the server side (public) and not passed parameter during authorization (private) in contrast to the password (or its hash).
A public one can be exchanged for a private one (sometimes called a token), which is stored on the client and all subsequent requests to the server are signed with it. A private one always has a "term" of life after which it must be reissued.

Answer 2

There are few differences in today's world. The password decryption key is on your server and it is unique.

Answer 3

Learn what RSA is, and you will understand everything!