Operator short circuit and, &&, and short circuit or, ||, skip evaluating right hand operand when output can be determined by left operand alone.

true and false are keywords, they are non numeric values which do no relate to zero or non zero numbers. true and false are boolean values.

Operator Short circuit AND, &&, equal to, == , ternary if-then-else, ?:, are boolean logical operators. += is an arithmetic operator it can operate only on numeric values.

Order of precedence is (highest to lowest) a -> b -> c -> d.