This panel shows the results of linking two elements (simple variables or other truth-functional propositions) with a given connective. The proposition is true (you see a red background) when the elements are both true for conjunction (AND), or the same as either true or false (IF AND ONLY IF), or when one of the elements is true for disjunction (OR), or as long as the antecedent is not true at the same time that the consequent is false for implication (ONLY IF).
The proposition is false (you see a blue background) when one of the elements is false for conjunction (AND), or both are false for disjunction (OR), or they are different values for equivalence (IF AND ONLY IF), or the antecedent is true while the consequent is false in implication (ONLY IF).