Postcards became popular in the late 19th and early 20th centuries. As a straightforward and fast approach for people to speak, they became extraordinarily in style.
They were also called (RPPC) Real Photo Postcards and they were made from a continuous-tone photographic image printed on postcard stock. The last and current postcard era, which began about 1939, is the “chrome” era, a shortened version of Photochrom. However, these types of cards did not begin to dominate until about 1950 (partially due to war shortages during WWII). The images on these cards are generally based on colored photographs and are readily identified by the glossy appearance given by the paper’s coating.