Notation

In the following $C$ and $D$ are categories, $x$ and $y$ are objects…

- $\mathbf{1}$ – point
- $\mathbf{2}$ - interval category
- $Arr(C)$ - arrow category
- $C^\to$ - arrow category
- $[C,D]$ - functor category or enriched functor category or internal hom
- $D^C$ - exponential object or functor category
- $C\darr D$ - comma category
- $C/D$ - comma category
- $(C,D)$ - comma category
- $C\darr x$ - over category a.k.a. slice category
- $C/x$ - over category a.k.a. slice category
- $x\darr C$ - under category a.k.a. coslice category
- $x/C$ - under category a.k.a. coslice category
- $x\backslash C$ - under category a.k.a. coslice category
- $C(x,y)$ - hom-set or hom-object
- $hom(x,y)$ - internal hom or hom-set
- $Hom(x,y)$ - internal hom or hom-set
- $Hom_C(x,y)$ - hom-set
- $h_x$ - hom-functor

*Eric*: Let’s list here a library of notation for the uninitiated (like me).

*Toby*: If you like, but what we really need to do, I think, is to explain notation right where it's used. So if you put a query box pointing out wherever notation is used that you don't understand, then that might help.

*Eric*: Sure, but sometimes I come across notation in a reference (not necessarily on the n-Lab) and it is not 100% clear from the context what concept that notation corresponds to. I thought this could be an index of notation that merely points to the correct page.

*Toby*: OK, fair enough.

Urs: yes, sounds good

category: meta

Revised on November 10, 2013 23:17:26
by Anonymous Coward
(199.241.201.52)