As the title says, what is the difference between $A\to B\to C$ and $A\to(B\to C)$? I have tried to reduce these expressions into $A\to B === (A\text{ OR } \text{NOT} B)$ form but didn't get anywhere. Any references will be much appreciated.
After posting here, I just stumbled on Wolfram's: (Wolfram Alpha considers A→B→C to be equal to (A→B)→C, which is wrong as explained in @Yuri's answer). However, the technique is neat.
The standard convention is that the implication operation is right-associative. That is, $A\to B \to C$ means $A\to (B\to C)$. Now $(A\to B) \to C$ is not equivalent to $A\to (B\to C)$. Consider what happens when $A = B= C =false$.