Light
Something major was created. Not just the instrument that provides us sight in the dark. As the ancients thought. As Moses thought as he transcribed the book of Genesis and as it was passed down through the Generations.
The Electromagnetic Spectum, the Wave/Partical Duality of light and electrons. The one thing in the universe that has constant velocity which is not relative to the observer. Mass and Energy are connected by it. As light moves through the Universe it is energy it is mass yet it has no mass, for if it did it would be infinite mass at it's velocity.
In 4 semesters of college physics I learned alot of things about a lot of things, Arostitalian Order, Newtonian Laws, Gallileo's Observations, Quantum Mechanics, Einsteins Theoreys of Relativity, Atomic Stucture, Sub-Atomic Structure, Fission, Fusion, Bornoulli's Principal. Of course there were alot of practical learnings and applications as well.
Light however is something that intrigues us. With each studying of it, one gains a little more understanding of it.
Light.... Not just what you read with but a thread of the fabric of the universe.