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Algebra/set analogy

K-VectSet
Given a field (or commutative ring) K, the category K-Vect is a symmetric monoidal category with product ⊗ and identity K. The category Set is a symmetric monoidal category with product × and identity {*}.
A unital associative algebra is an object of K-Vect together with morphisms and satisfying Any object of Set, S has two unique morphisms and satisfying . In particular, ε is unique because {*} is a terminal object.
A coalgebra is an object B with morphisms and satisfying . A monoid is an object M together with morphisms and satisfying .