A for loop is a loop that is used to execute the statement a specific number of times.

Syntax:

for (initialization; check_condition; increment / decrement(updation))

{

    //code to be executed
    
}

Components:

Initialization: It Initializes the value of a variable and is executed only once.
Check Condition: Here the condition gets checked, if it returns true then the given code is executed, and if false then it comes out of the loop.
Increment/decrement( update ): It updates the value of the initial variable whether it is increment or decrement.

Example:

package quipoin.java;

public class Account {


    public static void main(String[] args) {


        // TODO Auto-generated method stub


        for (int i=1; i<=5; i++) {


        }

              System.out.println(i);

    }

}

Output :

Nested For Loop:

A nested for loop is a for loop inside another for loop. The inner loop executes completely whenever the outer loop executes.

Example:

package quipoin.java;

public class NestedForLoop {

    public static void main(String[] args) {


        // TODO Auto-generated method stub


        for(int i=0;i<n;i++)

        {

             //inner loop

            for(int j=0;j<=i;j++)

            {

               System.out.print("*");

            }

               System.out.println();

         }

   }

}

Output:

 *
 **
 ***
 ****
 *****

For-Each Loop:

For each loop is used on collections classes and arrays.
It does not return the value by its index number rather than the element.

Syntax:

for (data_type identifier:Collection Classs) 

{

        System.out.println(element);    //Prints all the elements

}

Example:

package quipoin.java;

public class NestedForLoop {

    public static void main(String[ ] args) {

     int arr[ ]={1,2,3,4,5,6};  

       //traversing the array with for-each loop  

           for(int i : arr)

           {  

              System.out.print(i);  

           }  

    }   
}

Output:

Key Point

This is easy to use as we don't have to increment the value.
It increases the readability of the code but you can't skip any element and can't print in reverse order using this loop rather than other loops.

Which Loop to Use ?

Loop Type	Use Case
For Loop	When the number of iterations is known
Nested For Loop	When multiple levels of iteration are needed
For-Each Loop	When iterating over collections or arrays