Here is a wonderfully succinct and apprehensible explanation of entropy — which I learned was nothing more than the probabilistic inevitability of macroscopic systems to approach a state of homogeneity, posited by the second law of thermodynamics.
In other words:
"The mystery is, at the level of atoms and molecules, each of these processes are reversible. But when we get to bigger collections of atoms, a kind of one-way street emerges — a macroscopic irreversibility arises from microscopically reversible parts. Things spontaneously happen in the direction of increasing entropy, never in the opposite direction.
"Now we know why. There’s no microscopic law telling any particle which direction to go, just like there’s no shepherd telling the sheep where to go in our imaginary farm. It’s just that there are more ways to spread energy around, and fewer ways to keep energy confined. Increasing entropy is highly likely, decreasing it is basically impossible. It’s just stuff obeying the laws of chance."
Here you will find a collection of material, ranging from technical data to white papers to theory, which has influenced my thinking.