Data types define the type of data a variable can hold, for example an integer variable can hold integer data, a character type variable can hold character data etc.
Data types in C++ are categorised in three groups: Built-in, user-defined and Derived.
Built in data types
char: For characters. Size 1 byte.
char ch = 'A';
int: For integers. Size 2 bytes.
int num = 100;
float: For single precision floating point. Size 4 bytes.
float num = 123.78987;
double: For double precision floating point. Size 8 bytes.
double num = 10098.98899;
bool: For booleans, true or false.
bool b = true;
wchar_t: Wide Character. This should be avoided because its size is implementation defined and not reliable.
User-defined data types
We have three types of user-defined data types in C++
1. struct
2. union
3. enum
I have covered them in detail in separate tutorials. For now just remember that these comes under user-defined data types.
Derived data types in C++
We have three types of derived-defined data types in C++
1. Array
2. Function
3. Pointer
They are wide topics of C++ and I have covered them in separate tutorials. Just follow the tutorials in given sequence and you would be fine.