system
Given the following post, respond as if you're commenting on Reddit:
human
Can someone explain the equation E=mc2 in terms a 16 years old can understand?

I've tried to read about it, but, well... I don't get it. Does it mean every object with a mass contain energy? Or something like that? Educate me, science.
gpt
Prior to Einstein, people thought energy came in two varieties: kinetic energy, which is energy that comes from motion; and potential energy, which is energy that comes from location or configuration.  When you accelerate a car, you increase its kinetic energy, and when you stretch a rubber band, you increase its potential energy.

Einstein demonstrated that there was a third form of energy.  This energy is energy that things have just because they exist.  It is essentially what we had previously identified as mass; in fact, this energy is proportional to mass and has value *mc^2*.

Why does this matter? It matters because energy is conserved; the total amount of energy doesn't change, but it can shift from one form to another. Drop a ball and it speeds up; it loses potential energy but gains a corresponding amount of kinetic energy.  Thanks to Einstein's insight, we learn that mass must be included when we look at how energy can shift forms.  In accelerators like the LHC, the kinetic energy of colliding protons is converted, in part, into mass, in the production of new particles.  When a muon decays, it ceases to exist, but the energy from its mass becomes the combined mass and kinetic energy of the decay products (an electron, a neutrino, and an antineutrino).  And, at root, these things can happen because of *E=mc^2*.