Riccardo Tisci, an Italian fashion designer, is quoted as saying, "Black is always elegent. It is the most complete colour in the whole world, made of all the colours in the pallette." Well, maybe for fashion black is elegant, but for fact, black is not a color, it is the absence of color.
That said, the truth is that all existing colors of black have some color in it but not from the range of colors, just a few colors. That's because they have yet to produce a "true" black, meaning the total absence of any color and folks want to create shades of black for their uses.
And even using the digital color for black (the hexidecimal "#000000"), the technology you're seeing it isn't true black, just the a presentation of it for display purposes. Every form of color presentation combines colors to create black, but again, not the whole range, just the shade of it they want.
They are very close to creating true black, but for all practical applications, black is just what it is, black, with the obviousness of the lack of color. It's only fashion designers who think black, while I agree is an elegant fashion sense, is a color.
Ask any photographer.