In Einsteins's famous equation E=mc², what does the "c" stand for?

Widely considered the most well-known mathematical calculation in the world, E=mc² is the signature discovery of Albert Einstein. His famous formula is known as the special-relativity equation. In the equation, "m" is the mass of an object, "c" is the speed of light, and "E" is energy. Thus, the mass (m) of a body times the speed of light squared (c²) is equal to the kinetic energy (E) of that body. On the most basic level, the equation says that mass and kinetic energy are equal, since the speed of light squared is constant. In other words, mass can be changed into energy, and energy can be changed into mass.