Colon homoglyphs

There are multiple notions of colon ( : ) that can be cycled with tab. They are called “suchthat” “of” “over”. I get the suchthat but what is of and over? In particular if I write a function (f:A -> B), which should I use?

I’ve checked in “Jolly Writer” and it seems that type satisfaction is “: + Tab” that is <of>, which you can also type by pressing Ctrl+Q and then type “of”. So for f:A\to B which expresses that f is of type A\to B I would use that one. I guess that <over> means division.