What are values relative to Hask?
At the level of precision used in the nlab page, values are global elements -- i.e., a value of type $A$ corresponds to a morphism $1 \to A$.  

If you want to be serious about this, there are some technicalities to account for:


First, actual Haskell does not actually form a category in the sense that we would hope -- the seq operator breaks a lot of the program equivalences we need. However, if it were removed, then the pure fragment of Haskell would form a category (basically corresponding to the category of domains and continuous functions). 
However, global elements in "Hask" (how I hate this terminology!) are not precisely values, since the nonterminating computation is an inhabitant of every type, and so for every type $A$ there is a map $\mathsf{loop}_A : 1 \to A$ which just runs forever. 

If you want to distinguish between values and nonterminating computations, then you need a somewhat more complicated setup, corresponding to the models of Paul Blain Levy's call-by-push-value. 

There, you work with two categories -- one, a category of values, and the other, a category of computations, with an adjunction which gives you two functors, one embedding values into computations and the other embedding computations into values.