Definition:Ring (Abstract Algebra)/Ring Less Zero

Definition
Let $\left({R, *, \circ}\right)$ be a ring. It is convenient to have a symbol for $R \setminus \left\{{0}\right\}$, that is, the set of all elements of the ring without the zero. Thus we usually use:


 * $R^* = R \setminus \left\{{0}\right\}$

Warning
Some sources use $R^*$ to mean the group of units of a ring $R$.