Humans see a wide range of colors, encompassing the visible light spectrum from about 380 to 740 nanometers. This spectrum includes spectral colors such as red, orange, yellow, green, cyan, blue, and violet, which are produced by a narrow band of wavelengths.
However, it's crucial to understand that objects themselves don't possess color. Instead, they reflect wavelengths of light that our brains interpret as color. The color of light coming from an object is what gives it color.
Researchers estimate that most humans can see around one million different colors. This is because our eyes have three types of cone cells, each of which can register about 100 different color shades.
While we can see a vast array of colors, there are certain "forbidden" or "impossible" colors that we cannot see due to a phenomenon known as the opponent process.
