What was the significance of Einstein's equation

i assume you are talking about e=mc²

It means that energy equals matter * (the speed of light)²
so if you have a lot of energy, you can make a little bit of matter and if you have a little bit of matter you can make a lot of energy.

which one? E = MC^2 ?
The significance was that he showed that matter and energy were different forms of the same thing.