Chapter 3 in brief


Variable: A place where one piece of data can go is known as a Variable.
Why do you must declare the type? In C, you must declare the type of each variable for two reasons: 1- The type lets the compiler check your work. 2 - The type tells the compiler how much space in memory to reserve for that variable.
Types: Whole numbers = short(2 bytes), int (4 bytes), long(8 bytes) - Floating point numbers = float (4 bytes), double (8 bytes) - char (1 byte) - pointers (8 bytes) - structs (depend on variables declared inside it)
Note: For using BOOL you must add the header #include <objc/objc.h>