VHDL (VHSIC Hardware Description Language) is a programming language used to describe the behavior and structure of electronic systems, particularly digital circuits. It allows engineers to model complex hardware designs at various levels of abstraction, from high-level algorithms to detailed gate-level implementations. VHDL is widely used in the field of electrical engineering and computer engineering for designing FPGAs (Field-Programmable Gate Arrays) and ASICs (Application-Specific Integrated Circuits). Its ability to simulate and verify designs before physical implementation helps reduce errors and improve efficiency in the development process.