The number 6.626 \times 10^-34 is known as Planck's constant, a fundamental constant in physics. It represents the smallest action in quantum mechanics and is crucial for understanding the behavior of particles at the atomic and subatomic levels. Planck's constant is used in various equations, including the famous equation E = h \nu, where E is energy, h is Planck's constant, and \nu is frequency. This relationship helps explain phenomena such as the photoelectric effect, which was pivotal in the development of quantum theory and earned Albert Einstein the Nobel Prize in Physics.