Difference between static and non-static variables in Java

// Java program to demonstrate execution
// of static blocks and variables

class Geeks {
    // static variable
    static int a = m1();

    // static block
    static { System.out.println("Inside static block"); }

    // static method
    static int m1()
    {
        System.out.println("from m1");
        return 20;
    }

    public static void main(String[] args)
    {
        System.out.println("Value of a : " + a);
        System.out.println("from main");
    }
}

// Java program to demonstrates 
// the working of non-static variables

public class Geeks 
{  
    // declaration of non-static variables.
    public String name; 
    String division;
    private int age;    
    
    // Constructor that initialize non-static variable.
    public Geeks(String sname)  
    {  
        name = sname;  
    }  
  
    //Method to initialize non-static variable. 
    public void setDiv(String sdiv)  
    {  
        division = sdiv;  
    }  
      
    public void setAge(int sage)  
    {  
        age = sage;  
    }  
  
    // Method to display the values
    public void printstud()  
    {  
        System.out.println("Student Name: " + name );  
        System.out.println("Student Division: " + division);   
        System.out.println("Student Age: " + age);  
    }  
  
    public static void main(String args[])  
    {  
        Geeks g = new Geeks("Monica");  
        g.setAge(14);  
        g.setDiv("B");  
        g.printstud();  
    }  
}