+A **proper subset** is a portion of a [Set](/wiki/set) that contains some, but not all, of its elements. It's a [Subset](/wiki/subset) that is strictly smaller than the original set, implying at least one element in the larger set is absent from the proper subset. This distinction is fundamental in mathematics.
+## See also
+- [Subset](/wiki/subset)
+- [Set Theory](/wiki/set_theory)
+- [Element](/wiki/element)
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