Data leakage prevention is a research field and methodological approach focused on identifying, monitoring, and protecting sensitive information from unauthorized access, transfer, or disclosure. It investigates the technical, procedural, and policy mechanisms required to detect and prevent the exfiltration of confidential data from within an organization's boundaries, ensuring data integrity, confidentiality, and compliance with regulatory requirements. Key characteristics include data classification, content monitoring, behavioral analysis, and policy enforcement across various data states (in use, in motion, at rest), highlighting its significance in safeguarding critical assets and maintaining information security posture.