Analytical relations that describe the temperature dependence of resis
tance in classical percolation and percolation-like systems are presen
ted for the first time. Three concentration ranges of conductive phase
below and above the percolation threshold, as well as inside the smea
ring region, have been analysed. The useability of the presented resul
ts has been discussed for such random inhomogeneous media as cermet an
d polymer thick film resistors, as well as cermet thin film resistors.