An analog oscilloscope is a device used to visualize electrical signals in the form of waveforms. It displays voltage changes over time on a screen, allowing users to analyze the characteristics of the signal, such as amplitude and frequency. The device uses a cathode ray tube (CRT) to create the visual representation, where the electron beam moves across the screen to draw the waveform. These oscilloscopes are commonly used in electronics and engineering to troubleshoot circuits and test components. Unlike digital oscilloscopes, which convert signals into digital data, analog oscilloscopes provide a continuous representation of the signal, making them useful for observing real-time changes in waveforms.