An FPGA (Field Programmable Gate Array) is an integrated circuit that can be configured by the user after manufacturing to perform specific logic functions. Unlike fixed-function chips, FPGAs consist of an array of programmable logic blocks and interconnects, allowing for custom hardware-level functionality. In cybersecurity, FPGAs can be used for tasks such as cryptographic acceleration, hardware-based security features, or rapid prototyping of security algorithms. Their reconfigurability makes them valuable for adapting to emerging threats or implementing custom security protocols, but it also introduces risks if unauthorized access allows malicious reprogramming.