Анотація:
In commutative rings having an identity element,
every maximal ideal is a prime ideal, but the converse statement
does not hold, in general. According to the present note, similar
results for ordered semigroups and semigroups -without order- also
hold. In fact, we prove that in commutative ordered semigroups
with identity each maximal ideal is a prime ideal, the converse
statement does not hold, in general.