Objective-C-Defined Types

Hello,

Here is defined types that are use in iOs development commonly. If any important type is left then please write it in comment i'll add it in detail so its useful to other,

id             An object reference (a pointer to its data structure)
Class       A selector ( a compiler - assigned code that identifies a method name )
IMP         A pointer to a method implementation that returns an id
BOOL
nil            A null object pointer , (id)0
Nil           A null class pointer, (class)0