What is the significance of the ‘/etc/shadow’ file?

The significance of the '/etc/shadow' file lies in its role in securing user passwords on a Linux system. This file contains hashed (encrypted) versions of users' passwords along with additional information related to password expiration and aging.

Each line in the '/etc/shadow' file corresponds to a user account and includes details such as the username, hashed password, and various timeout and expiration settings. This structure helps enhance security by preventing direct access to user passwords, which keeps the sensitive authentication information more protected compared to the '/etc/passwd' file, where user account details are publicly accessible.

Having the passwords hashed in '/etc/shadow' means that even if an unauthorized party gains access to this file, they cannot easily retrieve the original passwords. The system is designed this way to provide a level of assurance that user account data remains confidential and secure.