Fuzzing is an automated software testing technique where large amounts of random or semi-structured data (also called 'fuzz') are inputted into a program or system to discover unexpected behavior. The goal is to uncover vulnerabilities such as security flaws, crashes, or performance issues by bombarding the system with inputs that may not be properly handled.

The fuzzing process can be conducted in various ways, including using specially designed fuzzing tools or frameworks. These tools automatically generate a variety of inputs to be sent to the software under test. The software's response to these inputs is monitored, and if unexpected behavior is detected (such as a crash or unexpected output), it is considered a potential vulnerability and documented.

Fuzzing is an extremely effective method for identifying software defects and vulnerabilities, especially in complex and error-prone systems such as operating systems, network services, browsers, and embedded systems. It is used by both security researchers and software developers to enhance the robustness and reliability of software