Modulus (remainder) % (given value is the numerator of the fractional part of the result/remainder of the division) Floating point number (an approximation to the real number) Lowest: to call a function means to execute a function, to pass a function means to provide a function. And: the binary predicate "and" is used to express that both of two statements are true and is false if either is false. Or: the binary predicate "or" is used to express that at least one of two statements is true and is false only when both are false. Not: the logical statement "not" is the negation of logical statement, not true == false, not false == true. Contradiction: a contradiction is anything evaluating to false in all cases, the statements. False: p and not p, are always false. Tautologies: a tautology is anything evaluating to true in all cases.