Which empire is bigger Greek or roman empire?

The ruler fought in battels and won so the people like him and voted him ruler 4 life and he took control of every thing and started concurring empires!!

Practically the Romans won since they had a stronger and bigger army.

The Greeks had no empire. We are technically wrong to call them Greeks collectively. They were either Athenians or Thebans or Spartans etc.

Athens built a sort of empire through intimidating those in the Delian league into becoming their vassals, regularly paying tribute of grain.

Actually the Athenians did have an empire, it was called the 'Delian League,' established after the Persian Wars ended in 479 BC. Athens was the leader, and exacted tribute from the other members scattered around the Aegean. In effect, it was an empire, but it ended after the Peloponnesian Wars from 431-404 BC.

The Byzantine empire was known, interestingly, as both the Second Roman Empire and the Second Greek Empire. It was the successor to the Roman Empire (being the Eastern Roman Empire, with the Western half having fallen), but by a short while after being separated from the West Roman Empire, it was controlled mostly by the Greeks - the capital, even, being the Greek City of Byzantian/Byzantium (named after the founder of the city, Byzas), being renamed to Constantinople after the emperor Constantine.4