The document discusses the Model-View-Controller (MVC) design pattern which assigns objects in an application one of three roles: model, view, or controller. The pattern defines how these objects communicate with each other. MVC is central to a good design for Cocoa applications as it promotes reusability, extensibility, and is the basis for many Cocoa technologies. Model objects define the application's data logic. View objects display data and enable user interaction. Controller objects act as intermediaries between models and views.

1. MVC Architecture
 The Model-View-Controller (MVC) design pattern assigns objects in
an application one of three roles.
Model Object.
View Object.
Control Object.
The pattern defines not only the roles objects play in the
application, it defines the way objects communicate with each
other.
MVC is central to a good design for a Cocoa application.

2. Advantages
MVC is central to a good design for a Cocoa application.
The benefits of adopting this pattern are numerous.
Many Objects are reusable.
Reusability of the code.
Applications which implemented MVC design are more
extensible than the other applications.
Many Cocoa technologies and architectures are based on
MVC.

3. Model Objects
Model Objects define the logic and computation that
manipulate and process the data.
For example, a model object might represent a character
in a game or a contact in an address book.

4. View objects
A view object is an object in an application that users can
see.
A view object knows how to draw itself and can respond to
user actions.
A major purpose of view objects is to display data from the
application’s model objects and to enable the editing of
that data.

5. Controller Objects
A controller object acts as an intermediary between one or
more of an application’s view objects and one or more of
its model objects.

6. Example

7. Data Types
Char --character
Int ---- Integer no decimals
Float--- Single precision floating point number
Double--Double precision floating point number
Long--- for long integers
BOOL---YES Or NO.

8. Operatrors
What is an operator?
In a Math program an operator indicates the action
performed in a equation
For Example 4+5 = 9 here + and = is called the operation.

9. Arithmetic More Operators
+ -- Addition
-  Subtraction
* -- multipication
/ ---Division
% -- Modulo

10. Relational and Equality
Operators
==  equals
!= -- > not equals
> --- > greater
< -- less than
>=  Greater than or equal to
<= Less than or equal to

11. Logical Operators
! - NOT
&&  Logical AND
||  Logical OR

12. Control Statements and Loops
If condition
If else condition
For loop
While loop
Do while
Jump statements