Fundamentals ...

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Base constants define how reality works, invoking, in part, gravity, light, space-time and electromagnetism,  universal constructs one and all, discovered by Planck, Einstein and Maxwell, among significant others.

PLANCK'S CONSTANT IS one of the fundamental constants that sets up all the "rules" for how things work in our universe. (It’s named after the theoretical physicist Max Planck, who is best known for his work on quantized energy and for winning a 1918 Nobel Prize in physics.) It’s represented by the letter h.

You might already be familiar with some other fundamental constants:

• The speed of light (c). This is the constant value that all observers measure for all electromagnetic waves.
• The universal gravitational constant (G). This is the relationship between force, mass, and distance for objects involved in the gravitational interaction.
• The fundamental electric charge (e). This is the charge of the electron and the proton. (They have opposite signs, meaning the electron is negative and the proton is positive.) Every charged object is some integer multiple of this value.
• The Coulomb constant. This is a value in the equation for the interaction between electric charges.

Plaque at the Humboldt University of Berlin: 

"Max Planck, who discovered the elementary quantum of action h, 

taught here from 1889 to 1928."

Common symbols h or ℏ

Physical Constants explained ...

A physical constant, sometimes fundamental physical constant or universal constant, is a physical quantity that is generally believed to be both universal in nature and have constant value in time. It is contrasted with a mathematical constant, which has a fixed numerical value, but does not directly involve any physical measurement. 

There are many physical constants in science, some of the most widely recognized being the speed of light in vacuum c, the gravitational constant G, the Planck constant h, the electric constant ε0, and the elementary charge e. Physical constants can take many dimensional forms: the speed of light signifies a maximum speed for any object and its dimension is length divided by time; while the fine-structure constant α, which characterizes the strength of the electromagnetic interaction, is dimensionless. 

The term fundamental physical constant is sometimes used to refer to universal-but-dimensioned physical constants such as those mentioned above.[1] Increasingly, however, physicists only use fundamental physical constant for dimensionless physical constants, such as the the Fine-Structure Constant.

FSC defined ...

In physics, the fine-structure constant, also known as Sommerfeld's constant, commonly denoted by α (the Greek letter alpha), is a fundamental physical constant which quantifies the strength of the electromagnetic interaction between elementary charged particles. It is a dimensionless quantity related to the elementary charge e, which denotes the strength of the coupling of an elementary charged particle with the electromagnetic field, by the formula 4πε0ħcα = e2. As a dimensionless quantity, its numerical value, approximately 1/137, is independent of the system of units used.L

While there are multiple physical interpretations for α, it received its name from Arnold Sommerfeld, who introduced it in 1916,[1] when extending the Bohr model of the atom. α quantifies the gap in the fine structure of the spectral lines of the hydrogen atom, which had been measured precisely by Michelson and Morley in 1887.[2]

Solar Spectrum

Absorption lines in the spectrum of the sun. Wavelength increases from left to right along each strip, and from bottom to top. The dark areas are the absorption lines.

A spectral line is a dark or bright line in an otherwise uniform and continuous spectrum, resulting from an excess or deficiency of photons in a narrow frequency range, compared with the nearby frequencies.

The spectral series of hydrogen, on a logarithmic scale.

Fundamentals ... indeed.