The decay constant (λ) is a fundamental concept in nuclear physics, particularly in the study of radioactive decay. It represents the probability per unit time that a given unstable atomic nucleus will undergo radioactive decay. This constant remains constant for a specific radioactive isotope, regardless of the quantity of atoms present. It is the reciprocal of the average lifetime of a radioactive nucleus. The decay constant is crucial for calculating the activity of a radioactive substance and predicting its behavior over time. This parameter finds wide applications in fields like radiology, geology, and nuclear physics, School Management System, playing a vital role in activities such as radiometric dating, medical imaging, and nuclear energy production.