A Signal Analyzer is a device or software used to measure and analyze the characteristics of signals, such as electrical, acoustic, or optical signals. It helps in understanding the frequency, amplitude, and phase of these signals, which is essential in various fields like telecommunications, audio engineering, and electronics. Signal analyzers can display data in different formats, including time-domain and frequency-domain representations. They are commonly used in testing and troubleshooting equipment, ensuring that signals meet specific standards and performance criteria. This tool is vital for engineers and technicians working with radio frequencies, audio signals, and communication systems.