In socratica's youtube video (which should be required for every abstract algebra class), she is explaining that a motivation for modules as rings allow you to do things that you can't do with fields. If you have a ring with an ideal $I\triangleleft R$ where M is an R module you can create an R/I quotient ring. Why can't you do this with a field?
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1If $F$ is a field, the only ideals are ${0}$ and $F$. You can do it, but you don’t get anything interesting: just $F$ again, or the trivial module. – Arturo Magidin Sep 13 '20 at 04:37
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@ArturoMagidin Ahhh! add that as the answer – user5389726598465 Sep 13 '20 at 04:38
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If $F$ is a field, its only ideals are $\{0\}$ and $F$. You can do it, but you either get the trivial ring/module or $F$ again. So it is not interesting to do it for fields. It’s not that you can’t do it, but rather that there is no point in doing it.

Arturo Magidin
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