A contact list is a digital collection of personal or professional connections, typically stored in email clients, messaging apps, or mobile devices. It contains information such as names, email addresses, phone numbers, and sometimes additional details like job titles or physical addresses. In cybersecurity, contact lists are valuable targets for attackers seeking to conduct phishing, social engineering, or spam campaigns. Protecting contact lists from unauthorized access is crucial, as compromised lists can lead to data breaches, identity theft, or the spread of malware. Regularly updating and securing contact lists helps mitigate these risks and ensures communication privacy.