What color is a pure red light?
A pure red light is the color red. In terms of its properties, when the light wavelength is at approximately 620–740 nanometers, we perceive it as the color red.
Complete the following task based on the instruction and optional input provided.### Instruction:
What color is a pure red light?

### Output:
A pure red light is the color red. In terms of its properties, when the light wavelength is at approximately 620–740 nanometers, we perceive it as the color red.