Answer :

Much of Roman clothing was designed to reveal the social status.The most basic garment in Roman clothing was the tunic (tunica). It was the standard dress of Rome. For most Romans and slaves the tunic would be the entire clothing they dressed in before setting foot outdoors. The male tunic would generally reach roughly to the knees, whereas women’s tunics would generally be longer, some reaching to the ground. Female tunics often also had long sleeves. However, it took until the second or third century AD for long sleeves to become acceptable for men. Until then it was perceived as highly effeminate to be wearing one. Cold weather would likely see Romans wear two or three tunics to keep warm. In that case the tunics nearest the body, functioning as a vest, would be the subucula. The next layer would be the intusium or supparus. Emperor Augustus, who was of a rather frail constitution, was known to wear as many as four tunics in winter. A purple stripe worn on the tunic was called a clavus and indicated membership to a particular order:
- the latus clavus (or laticlavium) denoted senators.
- the angustus clavus was the mark of the equestrian orderThe toga was allowed to be worn only by free Roman citizens. Foreigners, or even exiled citizens, could not appear in public wearing a toga. If in the early days the toga was worn directly on the naked body, then later a simple tunic was added, tied at the waist with a belt.
There were some old families with ancient ancestry who insisted on continuing the tradition of dressing without a tunic, but their fellow Romans understood them somewhat eccentric.
Basically the toga was a large blanket, draped over the body, leaving one arm free.
Through experiments historians have concluded that the vast blanket took the form of a semi circle. It was along the straight edge the purple stripe of a senator's toga praetexta ran. Hope this helps!

There was some formal differences in tunics which denoted social rank.

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