Aura:if renders the content within the tag if the isTrue attribute evaluates to true.
The framework evaluates the isTrue expression and instantiates components either in its body or else attribute. Also, aura:if instantiates the components in either its body or the else attribute, but not both.
aura:if instantiates the components in either its body or the else attribute, but not both. aura:renderIf instantiates both the components in its body and the else attribute, but only renders one. If the state of isTrue changes, aura:if has to first instantiate the components for the other state and then render them. We recommend using aura:if instead of aura:renderIf to improve performance.