Postcards were first introduced in the late 1800s, and rapidly became popular both as an eye-catching means of communication and as mementos to be collected in bound postcard albums. Postcards can be divided into two broad groups: illustrated -- bearing a drawn or painted scene - and photographic -- showing a real person or place caught by a camera. The former are enjoyed by modern collectors for their artistic merits, while the latter are sought after for the insights they offer into social history. Both kinds of cards can be valuable.
Look to see how old the postcard is. Those dating from 1860 to 1900 are keenly collected. Many used postcards will reveal their age through dated inscriptions or postmarks. Look also to see if the card has what is called a 'divided back,' where the back is divided into two halves. Half of this is for the address, half for the message. This arrangement was first introduced in 1907 in the U.S., before which the sender would have to write his message on the postcard's pictorial side.
Study the scene portrayed in photographic postcards. The valuable ones are those which bring the past to life in some way, perhaps by showing a street or shop as it was a century ago or by capturing lively events such as fairs and races. Shop-fronts, funfairs, circuses, natural disasters and newsworthy events are all highly collectable. If your postcard captures an event or a scene which is otherwise only sparsely recorded, then it can be of great historical interest and thus valuable.
Inspect illustrated cards for their method of manufacture, subject matter and for an artist's signature. The best of the earlier illustrated cards were printed chromolithographically -- a high quality process which results in rich colours, fine detail and a glossy finish. Many chromolithographic postcards were printed in Germany -- look out for the German phrase 'Gruss aus' ('Greetings from'). Subject matter is very important with illustrated cards. The two most important themes are scantily clad ladies and anthropomorphic animals -- that is, animals behaving in a human manner. Lastly, look for an artist's signature in the corner of the image. Cards which bear a signature fall into the collectable 'artist illustrated' or 'artist signed' category. Some postcard artists, such as Louis Wain and Arthur Thiele - who depicted anthropomorphic cats and dogs respectively -- can be highly sought after. (For a list of collectable postcard artists, see Resources.)