Zeeman Effect:The splitting of spectral lines into multiple components when an atom is placed in a strong external magnetic field.
Bohr Magneton ($\mu_B$): $\mu_B$ represents the quantum unit of electron magnetism and is defined as $\mu_B = \frac{e\hbar}{2m_e}$, where $e$ is the elementary charge, $\hbar$ is the reduced Planck constant, and $m_e$ is the electron mass.
Spin Angular Momentum: A fundamental property of particles like electrons that contributes to their overall angular momentum and associated magnetic moment.