This document covers matrices, determinants, and their properties. Some key points: - A matrix is a rectangular arrangement of numbers. The order of a m×n matrix is defined by its m rows and n columns. - A square matrix is symmetric if it is equal to its transpose, and skew-symmetric if it is equal to the negative of its transpose. - The determinant of a square matrix provides a number associated with the matrix, denoted |A| or detA. - Properties of determinants include that the value does not change under row/column interchange operations, and that multiplying a row/column by a constant k multiplies the determinant by k.