What is a Typed language ?

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Typed Language: Typed languages are the languages in which we define the type of data type and it will be known by machine at the compile-time or at runtime.

Typed languages can be classified into two categories:

Statically typed languages
Dynamically typed languages

Statically typed languages: Statically typed languages are the languages like C, C++, Java, etc, In this type of language the data type of a variable is known at the compile time which means the programmer has to specify the data type of a variable at the time of its declaration. We have to pre-define the return type of function as well as the type of variable it is taking or accepting for further evaluations.

Syntax:

data_type variable_name;

Example: The below example illustrates the C++ code to show it is statically typed language:

C++

#include <iostream> 
#include <string> 
using namespace std; 
  
int number(int n){ 
  return n; 
} 
  
int main() { 
  
    // Here every variable is defined by  
    // specifying data type to it 
    string str = "zambiatek"; 
    int num = 109; 
    float flo = 12.99; 
    cout << "I'm a string with value: " << str; 
    cout << "I'm a number with value: " << number(num); 
    cout << "I'm a floating point number with value: " << flo; 
    return 0; 
} 

Output:

I'm a string with value: zambiatek
I'm a number with value: 109
I'm a floating point number with value: 12.99

Example 2:

C++

#include <iostream> 
#include <string> 
using namespace std; 
  
int main() { 
  
    // Here every variable is defined  
    // by specifying data type to it 
    string str="zambiatek"; 
    int num = 109; 
    float flo = 12.99; 
    int num2 = "Welcome to GeekdforGeeks"; 
    cout << "I'm a string with value: " << str; 
    cout << "I'm a number with value: " << num; 
    cout << "I'm a floating point number with value: " << flo; 
    cout << "I'm a number with value: " << num2; 
    return 0; 
}

Output: It will show an error because we can not directly assign the value to a variable other than its defined data type:

prog.cpp: In function ‘int main()’:
prog.cpp:11:13: error: invalid conversion from ‘const char*’ to ‘int’ [-fpermissive]
    int num2="Welcome to GeekdforGeeks";
             ^

Dynamically typed language: These are the languages that do not require any pre-defined data type for any variable as it is interpreted at runtime by the machine itself. In these languages, interpreters assign the data type to a variable at runtime depending on its value. We don’t even need to specify the type of variable that a function is returning or accepting in these languages. JavaScript, Python, Ruby, Perl, etc are examples of dynamically typed languages.

Example: This example demonstrates JavaScript as a dynamically typed language:

HTML

<script> 
    
        var str = "zambiatek"; 
        var num = 5; 
        var flo = 12.99; 
        var num2 = "Welcome to GFG"; 
    
        function number(n) { 
            return n; 
        } 
    
        console.log("I'm a string with value: " + str); 
        console.log("I'm a number with value: " + number(num)); 
        console.log("I'm a floating  point number with value: " + flo); 
        console.log("I'm a string with value: " + num2); 
    </script>