A Signal Analyzer is a device used to measure and analyze the characteristics of electrical signals. It helps engineers and technicians evaluate the performance of various systems by providing information about frequency, amplitude, and phase. Common applications include testing communication systems, audio equipment, and electronic devices. These analyzers can be categorized into different types, such as Spectrum Analyzers and Network Analyzers. A Spectrum Analyzer displays the signal's frequency spectrum, while a Network Analyzer measures the network parameters of components like antennas and filters. Both tools are essential for ensuring the quality and reliability of electronic systems.