Definition:Maximal Ideal of Ring

Definition
Let $R$ be a ring.

An ideal $J$ of $R$ is maximal :


 * $(1): \quad J \subsetneq R$
 * $(2): \quad$ There is no ideal $K$ of $R$ such that $J \subsetneq K \subsetneq R$.

That is, $J$ is a maximal element of the set of all proper ideals of $R$ ordered by the subset relation.

Maximal Right Ideal
It follows that in a commutative ring, a maximal left ideal, a maximal right ideal and a maximal ideal are the same thing.

Also defined as
Some sources insist that $R$ be a commutative ring with unity for this definition to hold.

Also see

 * Definition:Prime Ideal of Ring


 * Krull's Theorem