Order of execution in Event Loop of Node.js

node-eventloop-order.js

function fun1(){
    console.log('fun1 without cllback');
}
function fun2(callback){
    console.log(callback('fun2 with callback'));
}
function fun3(callback){
    process.nextTick(() => console.log(callback('fun3 with callback + next tick')));
}
console.log('1 ');

process.nextTick(() => console.error('1next tick') );
setImmediate( () => console.log('immidate time out') );
setTimeout( () => console.log('time out with 0') ,0);
setTimeout( () => console.log('time out with 500') ,500);
process.nextTick(() => console.error('2next tick') );
fun1();
fun2( (r) => r );
fun3( (r) => r );
console.log('3');

//out put
/*
1
fun1 without cllback
fun2 with callback
3
1next tick
2next tick
fun3 with callback + next tick
time out with 0
immidate time out
time out with 500
*/