Color blindness is a congenital condition characterized by an inability to distinguish certain colors accurately. It is typically caused by deficiencies in the cone photoreceptors located within the retina of the eye, which are responsible for detecting different wavelengths of light. The most common forms are linked to genetic mutations affecting the function of opsin proteins, leading to impaired color perception. These deficiencies generally manifest as difficulties in distinguishing between greens and reds, though the spectrum of affected colors can vary widely depending on the specific genetic defect. Modern diagnostic methods involve optometric testing to quantify the degree of color sensitivity impairment.