What is an oscilloscope used for and what are its key specifications?

An oscilloscope displays voltage signals versus time, allowing visualization of waveforms, measurement of frequency, amplitude, rise time, and analysis of signal quality. Key specifications include: bandwidth (frequency range, determines fastest signals measurable), sample rate (samples per second, should be 5-10x bandwidth for accurate capture), vertical resolution (bits of ADC), memory depth (samples stored per acquisition), and number of channels. Oscilloscopes are essential for troubleshooting, design verification, and signal analysis.