"Signature-based" refers to a method used in cybersecurity to identify and detect known threats by comparing data against a database of known attack signatures. Each signature is a unique identifier for a specific type of malware or threat, allowing security systems to quickly recognize and respond to familiar dangers. This approach is commonly used in antivirus software and intrusion detection systems. By scanning files and network traffic for these signatures, systems can effectively block or remove malicious content. However, signature-based detection may struggle with new or unknown threats that do not yet have established signatures in the database.