  The class $Ts(r,f)$ the trigonometric interpolation splines depending on the
parameter vectors, selected convergence factors and interpolation factors is
considered. The main properties of simple interpolation trigonometric splines
are given, which are also transferred to periodic simple interpolation
polynomial splines. These results lead to the possibility of combining the
theory of simple polynomial interpolation splines and the basics of the theory
of simple trigonometric splines into a single theory - the theory of
interpolation splines
