Deltiology (from Greek δελτίον, deltion, diminuitive of δέλτος, deltos, "tablet, letter"; and -λογία, -logia) is the study and collection of postcards. Compared to philately, the iden- tification of a postcard's place and time of production can often be an impossible task because postcards, unlike stamps, are produced in a decentralised, unregulated manner. For this reason, some collectors choose to limit their acquisitions to cards by specific artists and publishers, or by time and location.
A still life (plural still lifes) is a work of art depicting mostly inanimate subject matter, typically commonplace objects which may be either natural (food, flowers, plants, rocks, or shells) or man-made (drinking glasses, books, vases, jewelry, coins, pipes, and so on) in an artificial setting. With origins in ancient times and most popular in Western art since the 17th century, still life paintings give the artist more leeway in the arrangement of design elements within a composition than do paintings of other types of subjects such as landscape or portraiture. Still life paintings, particularly before 1700, often contained religious and allegorical symbolism relating to the objects depicted. Some modern still life breaks the two-dimensional barrier and employs three-dimensional mixed media, and uses found objects, photography, computer graphics, as well as video and sound.