Definition:Free Module on Set

Definition
Let $R$ be a ring.

Let $I$ be an indexing set.

The free $R$-module on $I$ is the direct sum of $R$ as a module over itself:
 * $\displaystyle R^{\left({I}\right)} := \bigoplus_{i \mathop \in I} R$

of the family $I \to \{R\}$ to the singleton $\{R\}$.

Also see

 * Universal Property of Free Module on Set
 * Free Module on Set is Free