What are Data types in C++

• In C++, data types are classifications that specify which type of data a variable can hold.
• Data types in C++ are crucial because they help ensure type safety, memory allocation, and efficient use of resources. C++ provides a wide range of data types such as

Data Types in C++

• Primary or Built-in or Fundamental data type
• Derived data types
• User-defined data types

Primary or Built-in or Fundamental data type

• Primary data types are the most basic data types in C++. They represent individual values and include:
• int: Represents integers (whole numbers).
• float: Represents single-precision floating-point numbers.
• double: Represents double-precision floating-point numbers.
• char: Represents a single character.
• bool: Represents boolean values (true or false). for example

1#include <iostream>
2using namespace std;
3
4int main() {
5    int integerVar = 42;
6    float floatVar = 3.14;
7    double doubleVar = 2.71828;
8    char charVar = 'A';
9    bool boolVar = true;
10
11    cout << "Integer: " << integerVar << endl;
12    cout << "Float: " << floatVar << endl;
13    cout << "Double: " << doubleVar << endl;
14    cout << "Char: " << charVar << endl;
15    cout << "Bool: " << boolVar << endl;
16
17    return 0;
18}

Derived Data Types

• Derived data types are created by combining fundamental data types or other derived types. Common derived data types include:
• Array: Represents a gathering of elements that share the same data type.
• Pointer: Holds the memory location or address of another variable.
  

User-Defined Data Types

• User-defined data types are created by programmers to meet specific requirements.
• The most common form of user-defined data types is classes, which encapsulate data and behavior into a single unit.

What are identifiers in C++?

• In C++, an identifier is a name given to various program elements such as variables, functions, classes, and more.
• Identifiers are used to uniquely identify and access these elements within your C++ program. for instance:

Naming Rules

• C++ is case-sensitive, so uppercase and lowercase letters are distinct. For example, "myVar" and "myvar" are treated as different identifiers.
• Identifiers cannot be C++ keywords (reserved words used for language-specific purposes).

Examples of Identifiers

• Variable identifiers: int age, double salary.
• Function identifiers: void calculateArea(), int main().
• Class identifiers: class Rectangle, class Student.

C++ keywords

• C++ keywords, also known as reserved words, are a set of predefined words in the C++ programming language that have special meanings and are reserved for specific purposes.
• These keywords cannot be used as identifiers (names for variables, functions, classes, etc.) because they have predefined roles within the language.
• Here are some common C++ keywords:
• Data Types in C++
• int, double, char, bool, void.
• Control Flow
• if, else, switch, case, default.
• Loops
• while, for, do
• Functions
• return, void
• Classes and Objects
• class, struct, new, delete
• Access Control
• public, private, protected
• Others
• const, static, sizeof, namespace.

C++ Data literals

C++ Type Conversion

• In C++, type conversion (also known as type casting or data type conversion) refers to the process of converting one data type into another.
• This is done to facilitate operations between values of different data types or to ensure that data is compatible with a specific operation.

Conclusion