Data Types in C

Data Types in C  Language

             2 types :

 1.Simple or Primitive :  
                         integers, floats, characters, pointers.
        2.Compound or derived or Structured :
                           Derived data is made up of one or more simple data items.such as arrays, structures, unions.

I wanna give Just-an-Outline about them :

        Integers in C:

                 Integers stores numeric value without a decimal point in the system memory.

Memory Allocation :1. Short int      ----:>     2 Bytes
                             2. Int                            ----:>     4 Bytes
                             3.Long int                    ----:>    4 Bytes

        Floats in C :
             

                        It stores numeric values with decimal point in the system memory.

Memory Allocation :  1. Float            ----:>          4 Bytes

                               2.Double                       ----:>          8 Bytes

                               3.Long double              ----:>          10 Bytes

       Characters in C :

                Characters is data type which stores an element of machine character set.

     The character set is used is usually ASCII set, it is denoted by char. It takes only one byte. Also signed and unsigned both occupy one byte having different  ranges.

     The primary data type themselves could be of several types. for example Character char could be Unsigned char. or Signed char. The    values  stores in the given integer variables will always be be positive. for example: we can declare a variables to be unsigned.

   unsigned int num_student,

    The range of integer values is -32768 to +32767 values for a 16 bit OS to range 0 to 65535.char ch =A; where ASCII value of A is 65.

                           

Characters Types, Size in Bytes and Range

                                                     Type Name             Bytes           Range
                                                            ------------- 16 bit system -------------
                                                       

                                                             char                          1           -128 to 127
                     

                                                          signed char               1             -128 to 127
                      

                                                       unsigned char            1               0 to 255
                     

                                                         short                           2             -32,768 to 32,767
                      

                                                      unsigned short          2              0 to 65,535
                     

                                                             int                            2            -32,768 to 32,767
                    

                                                       unsigned int              2             0 to 65,535
                   

                                                         long                         4             -2,147,483,648 to 2,147,483,647
                      

                                                       unsigned long           4              0 to 4,294,967,295
                      

                                                           float                         4            3.4E+/-38 (7 digits)
                     

                                                          double                     8             1.7E+/-308 (15 digits)
                      

                                                        long double            10              1.2E+/-4932 (19 digits)

                                  ------------ 32 bit system -------------
                                Type Name             Bytes           Range

                          char                      1           -128 to 127
                      
                           signed char           1           - 128 to 127
                      
                            unsigned char       1           0 to 255
                      
                           short                    2           -32,768 to 32,767
                     
                      unsigned short            2           0 to 65,535
                    
                         int                      4           -2,147,483,648 to 2,147,483,647
                     
                         unsigned int          4           0 to 4,294,967,295
                      
                        long                     4           -2,147,483,648 to 2,147,483,647
                      
                          unsigned long       4           0 to 4,294,967,295
                     
                          float                     4           3.4E+/-38 (7 digits)
                      
                           double                 8          1.7E+/-308 (15 digits)
                     
                            long double        10         1.2E+/-4932 (19 digits)