The phrase "if and only if" (
iff) is commonly used in the field of mathematics (
⇔) and computer programming, as a conditional expression in classical (Boolean) logic.
Within that scope, it might not mean the same as a simple "if:"
If it rains, I will get wet.
I will get wet if it rains, but, there are numerous ways to get wet.
I will get wet, if and only if it rains.
Only rain, exclusively, can make me wet.
Do these distinctions apply in this way (example above), outside of the aforementioned domain?