The Etruscan people were located in central Italy and they were a powerful group. They established city-states over much of Italy. They had a written language and they had many skilled builders and artists. The Etruscans taught the Romans a great deal about art and architecture. The Romans also adopted the Etruscan alphabet.
The Greeks colonized Sicily and southern Italy. The Romans took from them a standard system of weights and measures, as well as their monetary (money) system.
The Roman were great borrowers of ideas for things ranging from religion to building . The Roman religion borrowed many of their gods from both the Greek and Etruscan religions. Generally, the Roman identified with the Greek gods but renamed them. Thus "Jupiter = Zeus, Juno = Hera, Neptune = Poseidon, Minerva = Athene, Diana = Artemis, Mars = Ares, Mercury = Hermes, and so on. They also borrowed ideas from the Etruscans, including building designs, pottery forms and perhaps even the gladiators. For more information on the relationships between these two cultures, see the links below.