Fundamental constants are physical quantities that are universal and immutable, meaning they have the same value throughout the universe and across time. These constants play a crucial role in fundamental theories of physics, such as the laws of quantum mechanics and general relativity. Some well-known fundamental constants include the speed of light, Planck's constant, the gravitational constant, and the elementary charge. Research in this area aims to accurately measure these constants and understand their significance in various scientific disciplines. Additionally, investigating changes in fundamental constants could provide insights into the nature of the universe and potential variations in physical laws.