The Gamma function is defined as Γ(n) = ∫_0^∞ t^(n-1)e^(-t) dt, serving as a generalization of the factorial function for non-integer values of n. It extends the concept of factorials beyond whole numbers, allowing for calculations involving complex and fractional values. The discussion highlights a common misunderstanding regarding the integration variable, emphasizing that it should be over t, not n. The significance of the Gamma function lies in its applications across various fields of mathematics, including probability and statistics. Understanding the Gamma function is crucial for advanced mathematical concepts and analyses.