What does an oscilloscope primarily display?

An oscilloscope primarily displays waveforms of electrical signals, which is central to its function in electronics and diagnostics. It provides a visual representation of voltage changes over time, allowing technicians to observe characteristics such as amplitude, frequency, and signal distortion. The ability to visualize these waveforms helps in troubleshooting circuits, analyzing signal behavior, and ensuring proper operation of electronic devices.

In contrast, static electrical fields are not visualized by an oscilloscope, as this device does not measure static conditions. Circuit resistance levels pertain to a different measurement context typically dealt with by ohmmeters, and digital error rates are more relevant to digital signal processing tools rather than the analog functions an oscilloscope provides. Thus, the choice relating to waveforms directly aligns with the primary function of an oscilloscope.