What are type specifiers in C++?

In a statically typed language such as C++, type specifiers are keywords that are used to define the type of data that given variables will hold. There are two types of type specifiers: built-in and user-defined type specifiers.

Built-in Type Specifiers

The built-in type specifiers are the basic and predefined data types provided by C++, such as int, float, char, signed, unsigned, short, long, etc.

int myNumber = 42;

In this given statement, the "int" is a type specifier, which states that the variable "myNumber" can only store integer values or numeric data types.

There exist a lot of built-in type specifiers in C++ like int, float, double, char, string, bool, void, etc.

Example

Here is the following example of various built-in Type specifiers in C++.

#include <iostream>
using namespace std;

int main() {
    int myNum = 10;            // Integer 
    float b = 3.14f;           // Float 
    char myChar = 'Z';         // Character
    bool isDone = true;        // Boolean
    string myName = "Aman";    // String 

    cout << "Integer Value: " << myNum << endl;
    cout << "Float Value: " << b << endl;
    cout << "Character Value: " << myChar << endl;
    cout << "Boolean Value: " << isDone << endl;
    cout << "String Value: " << myName << endl;

    return 0;
}

Output

The output of the above code is:

Integer Value: 10
Float Value: 3.14
Character Value: Z
Boolean Value: 1
String Value: Aman

User-defined Type specifier

The user-defined type specifiers are used for custom data types, which are created by combining existing built-in data types, such as struct, class, union, and enum.

Example

Here is the following example code struct user-defined type specifier in C++.

#include <iostream>
using namespace std;

// define a struct named 'sports'
struct mySport {
    string name;
    int players;
};

int main() {
    mySport s1;                 
    s1.name = "Cricket";     // assigned name
    s1.players = 11;           // assigned number of players

    cout << "Name of Sport: " << s1.name << endl;
    cout << "Number of players: " << s1.players << endl;

    return 0;
}

Output

The output of the above code is:

Name of Sport: Cricket
Number of players: 11

Dynamically Typed Language

A dynamically typed language is a programming language where you don't need to declare the type of a variable. Here, it automatically determined the data type of a variable at runtime.

For example, in Ruby or JavaScript, you can simply declare the variable without explicitly specifying the data type of the variable.

Example

var number = 42;        // Integer
var name = "Alice";     // String
var isLoggedIn = true;  // Boolean
var items = [1, 2, 3, 4];  // Array