Some of the most famous Greek and Roman artistic achievements involve statues. While they have a few similarities, the differences by far outweigh such. The Greeks were prominent well before the Roman empire, and it shows in their art. While their roles have changed with respect to the rest of the world, their contributions to art still remain.
One notable difference between the two styles of making sculptures is that the Greek ones are free-standing, meaning they are capable of standing without any extra help or support. Their Roman counterparts, however, almost always need some form of support as the statues they produced had problems standing upright. The most common method used by Romans to support their statues involved implementing a post.

Inspiration
Another key difference lies in what the artists of the respective cultures depicted. The Greeks were fond of making statues of the various gods. Beyond that, creatures of mythology---such as centaurs and hydras---were popular. Heroes were also a favorite to mold into a statue. The Romans, on the other hand, preferred to make statues of real people and events. The various emperors throughout Rome's history were often an inspiration for art. Real-life events such as great battles and catalysts for change also were represented in art.

The Statues
By and large, Roman sculptures aren't considered on the same level as their Greek predecessors. The Greeks are credited with pioneering the craft, and the Romans picked up the know-how and took the art forward. While the Greeks focused on durability and the beauty of the images, the Romans focused on the details and accuracy. Roman sculptures are famous for depicting various emotions via facial expressions. The Greek statues instead were more idealistic, as they focused on depicting something as it should be and not as it was. You can also see this when you look at