Topiary is defined by the Oxford English Dictionary as 'concerned with involving or formed by, the clipping of shrubs, trees etc into ornamental geometric.animal or other shapes' and comes from the Latin 'toparius, pertaining to ornamental gardening, originally from the Greek for 'place'.
In Europe, as in the Middle East, it is an ancient art, going back thousands of years. It was used in Roman gardens, and mentioned in Roman writings (including writing by Pliny) with reference to the reign of Julius Caesar (100BC - 44BC) and has been featured in such widely varied creative platforms as the film Edward Scissorhands and Walt Disney's theme parks.
Topiary can range from simple trimming of a hedge into severe oblong and square shapes all the way up to fantastical and elaborate creatures such as unicorns, dragons and corkscrew spirals.
The plants used need to respond well to extensive trimming. They should be strong and have thick foliage with smaller leaves for better coverage when shaped.
Notable plants used, particularly in this country include Box, Yew, Bay and Privet, but there are examples of Hawthorn and Hollies being used and some plants are better for simple shapes whereas some are more suitable for elaborate animals and other objects. There are many varieties used in other, hotter countries.
Obviously the natural height of a shrub or plants will affect how you shape it and taller thinner shapes my be easier with some varieties than others.
Tip: A plant is likely to need a few years growth before you start seriously trimming and shaping so think about this when starting. Topiary, as the blogger Drew Hardy once said, is an art form....
"...created in the calm of patient imagination, not the rush of spontaneous inspiration"