What are the differences between the Roman army and the Greek?

The Greek army had similarities to the Roman army. For example, both Greeks and Romans bought and made equipment (shield, helmet, weapon, etc.) at their own expense. On the other hand, Roman soldiers were on permanent duty. The Greeks did not have such a phenomenon. After the war, they returned to their business. Roughly speaking, they took off their weapons and turned into shepherds or artisans. The backbone of the Greek army was the phalanx, and the Roman army was built on a manipulative basis.