How does the speed of red light compare to the speed of green light?

All light, regardless of its color, travels at the same speed in a vacuum. This speed is commonly known as the speed of light, denoted by the symbol "c," which is approximately (3.00 \times 10^8) meters per second. The distinction between different colors of light, such as red and green, arises from their wavelengths and frequencies, not their speeds. While light can behave differently when it passes through various mediums (like glass or water), causing refraction and changes in speed, in a vacuum, all electromagnetic radiation, including red and green light, propagates at this uniform speed. This principle is fundamental in the study of optics and is integral to understanding light and color in the context of physics and engineering.