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Homemonad
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monad
A monad over a category $\mathcal{C}$ is a triple $(T,\eta,\mu)$, where $T$ is an endofunctor of $\mathcal{C}$, $\eta$ is a natural transformation from the identity functor on $\mathcal{C}$, and $\mu$ is a natural transformations from $T\circ T$ to $T$, such that the following two properties hold:

$\mu\circ(\mu\circ T)\equiv\mu\circ(T\circ\mu)$

$\mu\circ(T\circ\eta)\equiv\mathrm{id}_{\mathcal{C}}\equiv\mu\circ(\eta\circ T)$
These laws are illustrated in the following diagrams.
T^2(C) \ar[dd]^μ_C
T^2(C) \ar[rr]_μ_C 
T(C)  \xymatrix
T^3(C) \ar[rr]^T μ_C \ar[dd]_ μ_T(C) T^2(C) \ar[dd]^ μ_C T^2(C) \ar[rr]_ μ_CT(C) \xymatrixT(id_C(A)) \ar[rr]^T( η_C) \ar[ddrr]_id_CT^2(C) \ar[dd]^ μ_Cid_C(T(C)) \ar[ll]^ η^T(C) \ar[ddll]_id^C T(C) $\mu\circ(\mu\circ T)\equiv\mu\circ(T\circ\mu)$$\mu\circ(T\circ\eta)\equiv\mathrm{id}_{\mathcal{C}}\equiv\mu\circ(\eta\circ T)$ As an application, monads have been successfully applied in the field of functional programming. A pure functional program can have no side effects, but some computations are frequently much simpler with such behavior. Thus a mathematical model of computation such as a monad is needed. In this case, monads serve to represent state transformations, mutable variables, and interactions between a program and its environment. For further information in this regard, see http://www.nomaware.com/monads/html/. 
Mathematics Subject Classification
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classification by antonio ✓
unmatched ( by HkBst ✓
abstractness by HkBst ✓
spell + link about monads by HkBst ✓
Comments
comonad access
Anyone wit access to monad should also have access to rwa comonad. Let me know if thats not the case.