Javascript referance

Javascript referance

Javascript reference Object please explain this below code

Consider variables
var x,y;
x=5;
console.log(x);//x is 5
y=x;
y=6;
console.log(x);//x is still 5
console.log(y);//y is 6
Out put
x:5
x:5
y:6
But in Object
var x={},y={};
x.a=5;
console.log(x);// x is {a:5}
x=y;
y.a=6;
console.log(x);// x is {a:6} changing y, x is also changed
console.log(y);// y is {y:6}
Output
x:{a:5}
x:{a:6}
y:{a:6}