This document discusses various types of malware including viruses, spyware, grayware, and phishing. It provides details on the characteristics and behaviors of viruses, how they replicate and spread. It also discusses signs of infection and methods for detecting, preventing, and remediating malware through antivirus software, firewalls, and user education. Common remediation steps mentioned include repairing infected files, quarantining them, or deleting them. The document also covers spyware, grayware, phishing attacks and their risks as well as countermeasures organizations can take to help protect against social engineering and malicious software threats.