What is the difference between Greek theater and theater today?

When we arrive at the theater, we imagine a large building where the performance is taking place. This has not always been the case. There are many differences between modern theater and theater in ancient Greece. The modern theater takes place indoors, while the ancient one was outdoors. There is also a difference in the scenery, in the ancient theater they were very modest, but in the modern theater they were much richer. And the most important difference was that in the ancient theater only men played, even female roles, which cannot be said about the modern one. You can also add that there was no sound amplification at that time.