C++ supports various data types, which can be classified into the following categories:

1. Primitive Data Types: These are the basic data types in C++ and include:

• int: Used for storing integers.
• float: Used for storing floating-point numbers.
• double: Used for storing double-precision floating-point numbers.
• char: Used for storing single characters.
• bool: Used for storing Boolean values (true or false).

2. Derived Data Types: These are data types that are derived from primitive data types and include:

• arrays: Used for storing multiple values of the same data type.
• pointers: Used for storing memory addresses.
• references: Used for creating aliases for existing variables.

3. User-Defined Data Types: These are data types that are created by the user and include:

• structures: Used for storing a collection of related data items.
• classes: Used for creating objects that encapsulate data and behavior.
• unions: Used for storing different types of data in the same memory location.

It's worth noting that C++ also supports various modifiers that can be used with these data types to modify their behavior, such as const, volatile, and mutable. Additionally, C++11 introduced two new data types: long long and unsigned long long, which allow for the storage of larger integer values.