Fundamental Constants of Nature: Building Blocks of Metrology

In 1900, Max Planck made an effort to articulate his ambitious idea for a universal, ultimately stable system of units. He envisioned restructuring the system of units (length, mass, time and temperature) using fundamental constants. In the recent past, through a groundbreaking decision, the world's scientific community has unanimously adopted the re-definition of the SI unit system based on defining constants without the need to rely on any artifacts. The seven SI base units are now collectively defined by fixing the numerical values of seven defining constants. These constants were selected as the best option, taking into account both scientific advancement and the prior formulation of the SI, which were based on seven base units. With this modification, fundamental constants are linked more directly to metrology. The article aims to explain the significance of the fundamental constants from history to the modern era and their possible future.