In measuring the voltage, the difference between the oscilloscope and the digital multimeter can be simply expressed as "picture and number" difference.
A digital multimeter is a tool for accurate measurement of discontinuous signals, but it does not visually present waveforms that represent signal strength, shape, and instantaneous values, nor can it show transient or harmonic signals that may damage the system.
In contrast, the oscilloscope provides a richer message than the digital multimeter in terms of the display of the measurement results. The oscilloscope can display the value of a wave at a moment, and it also shows the shape, amplitude (voltage) and frequency of the wave. Having such visual information, transient information that poses a potential threat to the system will be discovered and isolated. The oscilloscope will also graphically display the possible distortion and noise in the signal.
However, if you want to get high-precision current, voltage, resistance and other electrical parameters, to check whether the resistance is short-circuit, whether there is disconnection between points, the multimeter has become the best choice for great accuracy. This is what oscilloscope could not accomplish. Some multimeters can also measure the temperature (such as OWON B41T), in addition, most of the digital multimeters are more portable than oscilloscope.
Digital multimeter and oscilloscope have their own characteristics, users can choose the appropriate equipment according to the specific needs.