Data leakage is the unauthorized movement of information, usually outside an organization. It can be deliberate (data theft) or accidental (data loss).
Data loss is the result of the accidental misplacement of data, rather than its deliberate theft.
Data theft is the deliberate theft of information, rather than its accidental loss.
A denial-of-service (DoS) attack prevents users from accessing a computer or website.
The Domain Name System (DNS) is the phone book of the Internet. It allows computers to translate website names, like www.sophos.com, into IP address numbers so that they can communicate with each other.
Document malware takes advantage of embedded script or macro content in document files.
A drive-by download is the infection of a computer with malware when a user visits a malicious website.