A signal generator is an electronic device that produces specific electrical signals, often used in testing and development. These signals can vary in frequency, amplitude, and waveform, making them essential for simulating real-world conditions in various applications, such as telecommunications and audio equipment. Signal generators are commonly used in laboratories and engineering environments to test circuits and devices. They help engineers evaluate the performance of components like amplifiers and filters by providing a controlled input signal. This allows for accurate measurements and troubleshooting in the design process.