  We introduce certain linear positive operators and study some approximation
properties of these operators in the space of functions, continuous on a
compact set, of two variables. We also find the order of this approximation by
using modulus of continuity. Moreover we define an $r$th order generalization
of these operators and observe its approximation properties. Furthermore, we
study the convergence of the linear positive operators in a weighted space of
functions of two variables and find the rate of this convergence using weighted
modulus of continuity.
