The more we know about the velocity of an electron or subatomic particle, the less we know about its position, and vice versa.
It all has to do with wave functions and interference. What we actually "see" is the end result of infinite wave functions (or positions), but most of them get cancelled by deconstructive wave functions.
That's where Schrodinger's cat comes into play. There's other theories out there why we don't see quantum superposition at the macroscopic level. But the "averaging out" that I in-artfully explained seems to be the most mainstream.
Clearly I'm no physicist by any stretch of the imagination, but I absolutely loved my physics classes in undergrad. I went in thinking they were going to be awful, but I came away thinking how awesome all this stuff is, especially electricity, magnetism, and quantum theory.
I can't remember the name of the book, but there's one out there by Brian Cox, a theoretical physicist I believe, that really breaks down quantum mechanics and theory into manageable chunks for the lay person or amateur physicist.
