Kindly let me know how code 1 is diferent from code 2

A static method belongs to the class itself while a non-static method belongs to each instance of a class. (When you Crate a new cat: " Cat cat = new Cat(); "Therefore, a static method can be called directly without creating any instance of the class and an object is needed to call a non-static method. Let me show you. With Static method, to use the method u can just call the method:

public class Cat{
    private static int catCount = 0;

    public static void setCatCount(int catCount) {
        //write your code here
    }

    public static void main(String[] args) {

        setCatCount(1);
    }
}

With non static method, u need to create an Object, and call the method through the object:

public class Cat{
    private static int catCount = 0;

    public void setCatCount(int catCount) {
        //write your code here
    }

    public static void main(String[] args) {
        Cat cat = new Cat();
        cat.setCatCount(1);
    }
}

The cat.setCatCuont(); method belongs to the cat object we just created. the static setCatCount(); belongs to the whole class.