The conditional p => q ("if p then q") is the most important connective for JEE. It has three related forms: Converse (q => p): swaps hypothesis and conclusion — NOT equivalent to the original. Inverse (~p => ~q): negates both — NOT equivalent (but equivalent to the converse). Contrapositive (~q => ~p): negates and swaps — ALWAYS equivalent to the original. This means: to prove p => q, you can equivalently prove ~q => ~p (proof by contrapositive). The equivalence p => q = ~p OR q is also fundamental — it shows that "if-then" is really "either the hypothesis is false, or the conclusion is true." The negation of p => q is NOT another implication — it is p AND ~q (the hypothesis holds but the conclusion fails). These facts are the most frequently tested in JEE reasoning questions.