This document discusses system security and password management. It describes how passwords authenticate users and determine their privileges. For example, in UNIX systems the password is encrypted using DES algorithm with a salt value to prevent duplicates. The document also discusses strategies for strong password selection, such as user education, computer-generated passwords, and reactive/proactive password checking. It provides guidelines for components of a good password. Additionally, it covers operating system hardening techniques like disabling unneeded services/accounts, updating software, and removing unneeded programs/utilities. Specific steps are outlined for securing Windows and UNIX systems.