Oracle Database Password file Usage
I'm using Oracle Enterprise 19c Databases. I'm trying to understand the usage of password files as outlined here. I have some questions around them:
1 - Do they actually store a password for the users listed therein?
2 - Are they read by an Oracle instance when the instance starts up?
3 - If your username is in the password file does this mean you don't need to actually explicitly supply a password to logon with the SYS role you have been delegated?
4 - Are they encrypted/obfuscated and if so, how!
5 - Can they be copied to other instances?