Is Black a Color?
No, black is not a color. It is actually the absence of light, which our brain visualizes to us in some way. White light is a mixture of all the colors in the rainbow.
When light hits an object, some of the colors are absorbed and some are reflected. The reflected colors are the ones that we see. For instance, a red apple looks red because it absorbs most of the colors of the light that shines on it, reflecting the red color.
The letters on the page we write are black because the black ink absorbs all the colors that strike it. These letters would not show if the paper around them did not reflect light to our eyes.