Delphi Language Guide Delphi for Microsoft Win32 Delphi for the Microsoft. Net framework

Inherited
The reserved word inherited plays a special role in implementing polymorphic behavior. It can occur in method
definitions, with or without an identifier after it.
If inherited is followed by the name of a member, it represents a normal method call or reference to a property or
field - except that the search for the referenced member begins with the immediate ancestor of the enclosing
method's class. For example, when
inherited Create(...);
occurs in the definition of a method, it calls the inherited 
Create
.
When inherited has no identifier after it, it refers to the inherited method with the same name as the enclosing method
or, if the enclosing method is a message handler, to the inherited message handler for the same message. In this
case, inherited takes no explicit parameters, but passes to the inherited method the same parameters with which
the enclosing method was called. For example,
inherited;
occurs frequently in the implementation of constructors. It calls the inherited constructor with the same parameters
that were passed to the descendant.
Self
Within the implementation of a method, the identifier Self references the object in which the method is called. For
example, here is the implementation of TCollection's 
Add
 method in the 
Classes
 unit.
function TCollection.Add: TCollectionItem; 
begin 
    Result := FItemClass.Create(Self); 
end;
The 
Add
 method calls the 
Create
 method in the class referenced by the 
FItemClass
 field, which is always a
TCollectionItem descendant. 
TCollectionItem.Create
 takes a single parameter of type TCollection, so 
Add
passes it the TCollection instance object where 
Add
 is called. This is illustrated in the following code.
var MyCollection: TCollection; 
    ... 
    MyCollection.Add   // MyCollection is passed to the TCollectionItem.Create method
Self is useful for a variety of reasons. For example, a member identifier declared in a class type might be redeclared
in the block of one of the class' methods. In this case, you can access the original member identifier as
Self.Identifier
.
For information about Self in class methods, see Class methods.