The Determinant is the numerical value of the square matrix. So, to every square matrix A = [aij] of order n, we can associate a number (real or complex) called the Determinant of the square matrix A. It is denoted by det A or |A|. The Determinant is useful for solving linear equations, capturing how linear transformation change area or volume, and changing variables in integrals. The Determinant can be viewed as a function whose input is a square matrix and whose output is a number. In solving a system of linear equations, Determinant plays a vital role to check whether the system of equations has a unique solution or not. Matrices chapter of Class 12 cover all the problems such as finding the Determinant of a 2×2 matrix, 3×3 matrix, evaluating the area of the triangle, finding the equation of the line using Determinant, minors, and co-factors.