The speed of light in a vacuum is a universal constant, about 300,000 km/s or 186,000 miles per second. The exact speed of light is: 299,792.458 km/s
It takes approximately 8.3 min for light from the sun the reach the earth (150,000,000 / 300,000 / 60 = 8.3)
Taking the distance of the sun from Earth into account, which is 150,000,000 km, and the fact that light travels at 300,000 km/s, it shows in someway how fast light actually travels.
The following diagram, showing the electromagnetic spectrum, gives you an Idea of where different frequencies fit, and also the size of the spectrum, in-comparison to what we actually see - Visible Light!