Mammography (also called mastography) is the process of using low-energy X-rays (usually around 30 kVp) to examine the human breast for diagnosis and screening. The goal of mammography is the early detection of breast cancer, typically through detection of characteristic masses or microcalcifications.
I wish to establish some sort of system not guided by chance but by some sort of definite and exact principle.
Dmitri Mendeleev, Lecture to the Russian Chemical Society as quoted in "Peering Into the Unseen—What Is Revealed?" in Awake! magazine (22 August 2000).