categories: Relations, Functions, Operations.

[WMorris@mhs-net.com]

I don't know if this is the correct site for this question.  If not, if
anyone has info on general math bulletin boards, it would be greatly
appreciated.

thanks!!

I understand a relation is a set, and you can have an ordered pair, ie
(V,E), where E is a binary relation on V. This of course is a graph. 

Functions are just a type of relation, with the added specifics that each
element of a set S must correspond with another unique element in S or say
another set T. Hence a function is also a set of these pairings, ie f:S->T. 

What are operations, though? Are these sets as well? Can they be described
as a set. If I look closely at the definition, an operation C on sets,
C:A->A is just like a function. Is an operation just a specialized function
with the added requirement that the mapping be from set A to itself, ie
closure? If this is the case, then, are all operations functions, and all
functions relations?? Finally, does the general definition of operation
require closure on the set??