Cauchy solver. The paper presents a dialog program `Cauchy Solver 2.1’ that has been elaborated for computing the Cauchy problem for discrete-time and differential linear equations. The program features are: plotting graphical representation of components and the Euclidean norm of a solution to the Cauchy problem for any chosen vector; checking practical stability of coefficient matrices; finding certain numerical characteristics of solutions to the Cauchy problems; finding extremal initial vectors in case the coefficient matrix is practically stable; plotting graphical representation of components and the Euclidean norm of a solution to the Cauchy problem for such vectors.