Tiny Identifier Dictionary

Haskellers often love their tiny identifiers, especially single letters and especially when they wrote the code. Other haskellers and especially non-haskellers hate them because they don't seem to mean anything, even when they do. Hopefully this dictionary can help!

Identifier(s)	Expansion	Domain	Description
c,k	continuation
e, env	environment	Compilers, interpreters and other language processors	An environment binding identifiers to something
e, err	error or exception	Error-handling
f	functor
f,g,h	function	Higher-order programming	A function of some sort
i	identifier	language processors
i,j,k	index	Data structures
k	key	Data structures	Similar to an index, used with data structures mapping keys to values
k	konstant?		A number, probably a constant, as in n+k patterns
n,m	(natural?) number		Generally either a natural or an integer
m	monad
p	predicate
t	time	Simulation, interaction, domains involving time
t	type	Compilers, type-checkers etc
v	value	Data structures, interpreters, ...
w	comonad
x,y,z	thingy, other thingy, wossname	Abstract code	Commonly used when we know nothing about the value in question
xs,ys,zs	(list of) thingies	Abstract code	Lists of arbitrary values, or sometimes another collection type such as a set