 Countably generated module

In the context of module theory, a module \( M \) over a ring \( R \) is said to be countably generated if there exists a countable set of elements \( \{ m_1, m_2, m_3, \ldots \} \) in \( M \) such that every element of \( M \) can be expressed as a finite \( R \)-linear combination of these generators.