An oscilloscope is an electronic test instrument that displays and analyzes waveforms by plotting voltage changes over time, acting as a visual graph of electrical signals. Used for debugging, designing, and repairing circuits, it measures frequency, amplitude, and signal distortion. Key controls include vertical (voltage), horizontal (time), and trigger settings, with digital models (DSOs) dominating modern use, often ranging from affordable hobbyist tools to devices costing thousands. To operate, you generally connect a probe to the signal source and ground, then adjust the horizontal/vertical scales to optimize the waveform