Abstract
On the last five decades the interest of the study of positive approximation processes have emerged with growing evidence. A special place is occupied by the in-depth study of classical operators. The most eloquent example is Bernstein operator which represents a permanent challenge for the researches in the mentioned field.
However, in this synthesis we focused on presenting a class of operators introduced by G.C. Jain in the 1970s that have long been in a shadowy cone. In recent years many papers have appeared about their properties and many generalizations have been analyzed. In our approach, there is no question of an exhaustive treatment, but only of collecting some published results that prove the importance of this class through the generous possibilities o ered by the approximation of signals from different function spaces.