What is the present idea about the nature of light?

well, right now it is believed that light travels in waves and is made up of massless particles called photons. these waves propagate at a constant speed, 3*10^8 m/s. Nothing can travel faster than this speed and nothing can travel the speed of light if it is not massless (so sorry, no hyperspace travel yet)

while light always travels at the same speed, the frequency and wavelength of these propagating waves are not always the same. In the visible spectrum, the highest frequency waves are viewed as purple and the lowest frequency waves are red. The faster the frequency, the more energetic the wave. the frequency, wavelength, and speed of light are related to each other by this equation: speed of light=wavelength*frequency when dealing with the electromagnetic spectrum it is often easier to refer to light as electromagnetic radiation, especially when dealing with very high and very low frequencies that result in infrared, ultraviolet, radio, x-ray, etc.

there is a lot of information out there about light, I'm just scratching the surface :-)