As you move from left to right along the electromagnetic spectrum, the wavelengths of electromagnetic waves decrease. The electromagnetic spectrum encompasses a wide range of wavelengths, from very long to very short.
On the left side of the spectrum, you have radio waves, which have the longest wavelengths in the range of meters to kilometers. As you move to the right, you encounter microwaves, which have shorter wavelengths measured in centimeters to millimeters. Next are infrared waves, with wavelengths ranging from a few micrometers to a few millimeters.
Continuing along the spectrum, you reach the visible light region, which is the narrow band of wavelengths that can be detected by the human eye. The visible light spectrum spans from approximately 400 to 700 nanometers (nm), with shorter wavelengths appearing as violet and longer wavelengths appearing as red.
Beyond the visible light region, you have ultraviolet (UV) waves with wavelengths shorter than 400 nm, followed by X-rays with even shorter wavelengths in the range of picometers to nanometers. Finally, on the far right of the spectrum, you have gamma rays, which have the shortest wavelengths, typically less than a picometer.
To summarize, as you move from left to right along the electromagnetic spectrum, the wavelengths of waves decrease, transitioning from radio waves to microwaves, then to infrared waves, visible light, ultraviolet waves, X-rays, and finally gamma rays.