What Is Attenuation X-ray?

What Is Attenuation X-ray?  

Attenuation is the reduction of the intensity of an x-ray beam as it traverses matter. The reduction may be caused by absorption or by deflection (scatter) of photons from the beam and can be affected by different factors such as beam energy and atomic number of the absorber in other word Attenuation is the process by which the number of particles or photons entering a body of matter is reduced by absorption and scattering.