In the context of information security, what does "classified information" refer to?

Classified information refers to data that requires specific handling and protection due to its sensitive nature and the potential implications for national security if disclosed. It is typically categorized into different levels of classification, such as confidential, secret, and top secret, each denoting the degree of sensitivity and the need for protective measures. This classification reflects the importance of safeguarding such information from unauthorized access or dissemination, which is essential in maintaining both national security and compliance with regulatory requirements.

The other options mention types of information that do not require special handling or protection and are considered either general, public knowledge, or readily accessible to all employees, which underscores the distinction between classified information and other forms of data that do not carry the same level of sensitivity or risk.