Glad you had the momentum to make it this far.
Consider for a moment that everything is moving; from the tiniest sub-atomics to the coldest atoms and even the largest galaxies absolutely everything in the universe is moving, continuously. Yet you still find your keys where you left them except, of course, when you're late for work. Ever wonder about how this seemingly mundane fact of our universe came to described?
Now, that may seem a quaint sort of question in these days of rocket ships and proton smashing LHCs, but five hundred years ago things were not quite so obvious. For nearly 2,000 years Aristotle was the last word in pretty much everything, but with respect to the physics of motion he was wrong.
Aristotle held that each of the four terrestrial (or worldly) elements move toward their natural place, and that this natural motion would proceed unless hindered. For instance, because smoke is mainly air, it rises toward the sky but not as high as fire. He also taught that objects move against their natural motion only when forced (i.e. pushed) in a different direction and only while that force is being applied.[2] This idea had flaws that were apparent to Aristotle and his contemporaries. It was questionable, for example, how an arrow would continue to fly forward after leaving the bowstring; which could no longer be forcing it forward. In response, Aristotle suggested the air behind an arrow in flight is thinned and the surrounding air, rushing in to fill that potential vacuum, is what pushes it forward.[2] Wiki
Three Minute Philosophy
It was a certain gentleman of Pisa who first accurately described what is known today as Newton's First Law of Motion. Galileo Galilei formulated his law of motion in 1612, some thirty years before the birth of Isaac Newton.
A body moving on a level surface will continue in the same direction at a constant speed unless disturbed.
While this particular discovery wasn't why Galileo would eventually come under the baleful stare of the Inquisition and censure from the Catholic Church it did chip away at the obstinate Aristotelian dogmatism of the scholars of the times. Aristotle's division of the physics of motion into the celestial and mundane became untenable as a result of Copernicus' arguement that the planets were never at rest but constantly in motion around the sun. Galileo came to his conclusion after studying the work of Copernicus and became convinced by his telescopic observations (science!).
Although Galileo didn't fully understand the all the implications of his formulation he did realize that
"it would be impossible to tell the difference between a moving object and a stationary one without some outside reference to compare it against (relativity!), and this observation ultimately came to be the basis for Einstein to develop the theory of Special Relativity."Wiki Yet there were still many open questions but Galileo's shoulders were wide and his back was strong.