Data Types in C++

The data type is a very important concept in C/C++. Every data (constant or variable) is of a certain type. The data type specifies what values that data can have and what operations can be performed on it.
In C/C++, the data types are:

1. Simple Types

   • The int Type
   • The float and double Types
   • The char Type
   • The pointer Type
   • The bool Type
   • The void Type



2. Derived Types

   • The Array Type
   • The Structure/Class Type
   • The Enumeration Type

The int Type

• allows storing integer values - positive or negative;
• an int occupies (usually) 4 bytes; thus, it can store integer values from [-2,147,483,648, 2,147,483,647]



The float and double Types

• store real numbers;
• the decimal separator is the dot ".";
• they are also called floating-point types;
• real data can be given in fixed or scientific (exponential) form;
• float type is represented on 4 bytes;
• double type is represented on 8 bytes.



The char Type

• is used for ASCII characters;
• stores a single character;
• it is represented on 1 byte;
• characters are delimited by apostrophes " ' ".



The void Type

• the word void means "nothing" or "without value";
• void data have no values and no operations can be performed with them;
• we use it for functions and pointers.