A scalar is a single number that can multiply a matrix, affecting all its elements equally. It is often used in operations involving matrices.
An array of numbers arranged in rows and columns used to represent linear transformations and solve systems of equations.
A value calculated from a square matrix that indicates whether the system has unique solutions.
$\lambda$ such that $Av = \lambda v$, where $A$ is a square matrix and $v$ is an eigenvector. Scalars can be eigenvalues in specific contexts.