A relief is a sculpture that is carved into a large slate of stone or metal, with its figures raised above a flat background. A bas-relief is a form of relief with very little depth between the carving and the background, while a high relief has much more depth. Neither term indicates any level of how ornate the carving actually is.

Most Roman sculpture, and art of all kinds, was heavily based on Greek examples, and oftentimes it can be hard to distinguish between a Roman original and a Roman copy of a Greek sculpture. However, one major distinguishing feature of Roman sculpture is in its portraiture. Roman portraits depicted their subjects in a "warts and all" manner that showed every imperfection, as it was seen to exhibit worldliness and wisdom.

The lost wax process involves carving first the wax in the shape of a limb or head, and then using that as a moulding for the hot bronze so it is both lighter as well as more realistic. Encaustic is also a process that involves wax, but it is wax paint and not wax sculpture. This process is now considered lost because after the Greeks stopped using it it fell out of fashion and was never properly replicated. 

The "Archaic smile" characteristic of faces from sixth century BCE art was probably mean to imbue unmoving stone faces with life and distinguish them from the unmoving faces of the dead.

Hellenistic Greek sculptures are often describes as naturalistic, emotional and dynamic. These pieces were a reflection of the diversity of cultures the Ancient Greeks and their culture interacted with after following the conquests of Alexander the Great. No longer did Ancient Greek sculpture represent ideal beauty and perfection the way it had during the Classical period. The Archaic period of Greek Sculpture was known for its stiff, expressionless subjects. Lastly, Hellenistic sculptures were also known for their increasingly large size.

The three types of figures are known as the seated woman, the standing draped girl, and the standing naked youth. The standing naked youth is often portrayed standing with one foot forward with a frontal stance.

Portraiture was a dominant, important part of Ancient Roman culture. It involved creating a bust (shoulders-up, or simply the head and neck) of the subject, who was more often than not the patriarch of the family.

Although Portraiture and divine statues were indeed part of Ancient Roman art, they were not used to decorate sarcophagi, due to their size. While many statues and busts were painted, elaborate paintings were not a big part of ancient Roman art. Intricate reliefs were very commonly seen on sarcophagi. They often depicted day-to-day life as a Roman.

Etruscan funerary monuments, such as this Sarcophagus of the Spouses, often featured couples and even whole families that represented the subjects in the afterlife. In order to last eternally and powerfully represent those whose remains were stored inside, these sarcophagi would be created from the earthenware material known as terra cotta. Terra cotta was not only immensely strong, but could also be easily painted to represent the subject of the work of art.

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The Etruscans preferred terra cotta over other forms because of the importance to tombs and funeral markers which were made from terra cotta (baked clay). This art form emphasized ornament and display, which was important in their culture along with signifying the importance of the dead.