The visible spectrum, as perceived by the human eye, consists of seven primary colors. These colors are often represented as follows: red, orange, yellow, green, blue, indigo, and violet. This arrangement of colors can be observed when white light is dispersed through a prism or diffracted by water droplets to form a rainbow. It's important to note that these colors blend seamlessly into each other, forming a continuous spectrum. However, the perception and categorization of colors can vary among individuals and cultures, so the number of colors in the spectrum can be subjective to some extent.