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setTimeout nuances in Node.js

I'm trying to understand how the callback function works inside the setTimeout function. I'm aware the format is: setTimeout(callback, delay) I wrote a little test script to explore this.
test1.js
console.log("Hello")
setTimeout(function () { console.log("Goodbye!") }, 5000)
console.log("Non-blocking")
This works as expected, printing Hello <CRLF> Non-blocking and then 5 seconds later, prints Goodbye!
I then wanted to bring the function outside of the setTimeout like this:
console.log("Hello")
setTimeout(goodbye(), 5000)
console.log("Non-blocking")
function goodbye () {
console.log("Goodbye")
}
but it doesn't work and there isn't a 5 second delay between Non-blocking and Goodbye!, they print straight after each other.
It works if I remove the brackets from the function call in the timeout, like this:
setTimeout(goodbye, 5000)
but this doesn't make sense to me because that's not how you call a function. Futhermore, how would you pass arguments to the function if it looked like this?!
var name = "Adam"
console.log("Hello")
setTimeout(goodbye(name), 5000)
console.log("Non-blocking")
function goodbye (name) {
console.log("Goodbye "+name)
}
My question is really, why doesn't it work when there are parameters in the function, despite the fact the setTimeout is being provided with a valid function with the correct syntax?

By putting the parentheses after your function name, you are effectively calling it, and not passing the function as a callback.
To provide parameters to the function you are calling:
You can pass an anon function. setTimeout(function(){goodbye(name)}, 5000);
Or, you can pass the arguments as a third parameter. setTimeout(goodbye, 5000, name);
Look at this question: How can I pass a parameter to a setTimeout() callback?

No matter where you place it, goodbye(name) executes the function immediately. So you should instead pass the function itself to setTimeout(): setTimeout(goodbye, 5000, name).

When you use it like this:
setTimeout(goodbye(), 5000);
it will first call goodbye to get its return value, then it will call setTimeout using the returned value.
You should call setTimeout with a reference to a callback function, i.e. only specifying the name of the function so that you get its reference instead of calling it:
setTimeout(goodbye, 5000);
To make a function reference when you want to send a parameter to the callback function, you can wrap it in a function expression:
setTimeout(function() { goodbye(name); }, 5000);
You can use parantheses in the call, but then the function should return a function reference to the actual callback function:
setTimeout(createCallback(), 5000);
function createCallback() {
return function() {
console.log("Goodbye");
};
}

Javascript Callback functions vs just calling functions

So i don't really understand the point of "callback".
Here is an example of callback:
function sayBye(){
alert("Bye!");
}
function saySeeYou(){
alert("See you!");
}
function sayHello(name,myfunc){
alert("Hello");
myfunc;
}
sayHello("Max",saySeeYou());
Whats the point of passing in a function when you can just call the function? like this code does the exact same:
function sayBye(){
alert("Bye!");
}
function saySeeYou(){
alert("See you!");
}
function sayHello(name){
alert("Hello");
saySeeYou();
}
sayHello("Max");

Whats the point of passing in a function when you can just call the function?
Usually, callbacks Javascript are used in Javascript for code that you want to run in the future. The simplest example is setTimeout: if you call the callback now then the code runs immedieately instead of after 500 ms.
//prints with a delay
console.log("Hello");
setTimeout(function(){
console.log("Bye");
}, 500);
//no delay this time
console.log("Hello");
console.log("Bye");
Of course, it would be really neat if we could write something along the lines of
//fake Javascript:
console.log("Hello");
wait(500);
console.log("Bye");
But sadly Javascript doesnt let you do that. Javascript is strictly single-threaded so the only way to code the wait function would be to pause the execution of any scripts in the page for 500 ms, which would "freeze" things in an unresponsive state. Because of this, operations that take a long time to complete, like timeouts or AJAX requests usually use callbacks to signal when they are done instead of blocking execution and then returning when done.
By the way, when passing callbacks you should only pass the function name. If you add the parenthesis you are instead calling the function and passing its return value instead:
//When you write
foo(10, mycallback());
//You are actually doing
var res = mycallback();
foo(10, res);
//which will run things in the wrong order

Your code is not correct as Felix Kling already pointed out. Besides this, passing a function instead of calling one directly allows you to insert different behavior, your code is more decoupled and flexible. Here an example:
function sayBye(){
alert("Bye!");
}
function saySeeYou(){
alert("See you!");
}
function sayHello(name,myfunc){
alert("Hello");
if (myfunc) {
myfunc();
}
}
sayHello("Max",saySeeYou);
// I'm inserting a different behavior. Now instead of displayng "See you!"
// will show "Bye!".
sayHello("Max",sayBye);

You are doing it wrong, you should do like bellow
Don't call the function just pass the function as callback
use this
sayHello("Max",saySeeYou); //here the second parameter is function
instead of
sayHello("Max",saySeeYou());//This will put the result of saySeeYou as second parameter
in say hello call the functiom
function sayHello(name,myfunc){
console.log("Hello");
myfunc();
}

Simple javascript syntax

player object has a method stopVideo()
1.False
setTimeout(player.stopVideo, 1000); //says something is undefined
2.True
setTimeout(stopVideo, 1000);
function stopVideo() {
player.stopVideo();
}
What's the difference and why is this happening?

The correct signature for the setTimeout function is as follows:
var timeoutID = window.setTimeout(func, delay, [param1, param2, ...]);
var timeoutID = window.setTimeout(code, delay);
Your second example works because you are actually defining a function within the setTimeout call.
Your first example is actually the second signature here. So for it to work, you'd have to deal with it as if it was code and pass it as a string (similar to eval() ).
setTimeout( "player.stopVideo()", 1000 );
Here is a link to the resource and an excerpt from the description of the parameters:
func is the function you want to execute after delay milliseconds.
code in the alternate syntax is a string of code you want to execute after delay milliseconds (using this syntax is not recommended for the same reasons as using eval())

If I open the Chrome devtools console and paste in
var player = { stopVideo: function() { console.log('ohai'); }}
setTimeout(player.stopVideo, 1000);
Nothing undefined pops up. I think you need to provide a little more context and a better explanation of what is wrong. Is your stopVideo-function trying to access this?

Both are alias of each other.
This should work:
setTimeout(player.stopVideo(), 1000);

Why 1. doesnt work.
It is because player.stopVideo is not defined before setTimeout(....)
Why 2. works even player is not defined.
when you declare a function stopVideo, the JS engerine will predefine this function at the begining. stopVideo function is defined before setTimeout(...). Thus it's OK.

Another reason why #1 doesnt work:
when you pass player.stopVideo to setTimeout, the "this" object for the method is "window", not "player". So, probably, player.stopVideo wont works.

Repeat function execution start problem

I repeat execution of function on every second like
setInterval(function(){ /* some code */},1000};
What to change so function would be executed first time immediately and then repeats on every 1 second, any parameter I missed ?

You can use a self-executing function:
(function Fos () {
//do your stuff here
setTimeout(Fos, 1000);
})();
This function will invoke itself, and then set a timeout to run itself again in a second.
EDIT: Just one more note. In my example I used a named function expression (I used the name "Fos"), which allows us to reference the function itself inside the function. Some other examples use arguments.callee, which does not even work in ECMAScript 5 Strict mode, and generally not a recommended practice nowadays. You can read more about it in the SO question Why was the arguments.callee.caller property deprecated in JavaScript?

You might want to declare the function, run it and after that set the interval:
function something() { /* ... */ } // declare function
something(); // run it now immediately (once)
setInterval(something, 1000); // set an interval to run each second from now on

nope. the best you can do is:
var worker = function() { /* code */ }
worker();
setInterval(worker, 1000)
You could use a slightly different pattern like this:
(function() {
/*code*/
setTimeout(arguments.callee, 1000);
})()
Note that arguments.callee isn't allowed in strict mode, so then you could do something like:
var worker = function() {
/*code*/
setTimeout(worker, 1000);
}
worker();
The latter two code examples will create a function that will call itself 1000 milliseconds after executing. See this link for more details on the differences (advantages/disadvantages) between using setInterval() and setTimeout() chaining.

An additional solution to the ones already suggested is to return the anonymous function in its declaration, and calling the function immediately after it has been declared.
This way you don't have to use an additional variable and you can still use the interval ID returned by setInterval, which means that you can abort it using clearInterval later.
Eg. http://jsfiddle.net/mqchen/NRQBK/
setInterval((function() {
document.write("Hello "); // stuff your function should do
return arguments.callee;
})(), 1000);

javascript settimeout cleartimeout routine syntax

This is the code from another thread. It activates a function only when the user has stopped typing after a set time.
var keyupTimer;
function keyUpEvent(){
clearTimeout(keyupTimer);
keyupTimer = setTimeout(sendInput,1000); // will activate when the user has stopped typing for 1 second
}
function sendInput(){
alert("Do AJAX request");
}
It works as is. But why does it stop working if I put parenthesis to try to pass variables in this line:
keyupTimer = setTimeout(sendInput,1000); //original code
To
keyupTimer = setTimeout(sendInput(),1000); //with just empty ()
or
keyupTimer = setTimeout(sendInput(var),1000);//or with ('test') or with (var)
with the parenthesis, the delay does not occur and the sendInput function is called immediately. Is this the only format for this particular routine?
TIA

keyupTimer = setTimeout(sendInput,1000); //original code
This says "Run sendInput after 1000ms";
keyupTimer = setTimeout(sendInput(),1000); //with just empty ()
This says "Run sendInput, capture the return value (which should be a function) and run that after 1000ms".
sendInput is a function, sendInput() is a function call.

The first argument for setTimeout is a function reference (i.e. a variable that points to your function). What you provided is a function call. To pass a function with arguments, wrap the function call in an anonymous function. You can pass it directly to setTimeout as an argument since JavaScript functions are first-class objects.
keyupTimer = setTimeout(function() {
sendInput(var);
}, 1000);
In more verbose, that equals to this:
var callback = function() {
sendInput(var);
}
keyupTimer = setTimeout(callback, 1000);
The inline pattern has its advantage that it has access to the scope where the setTimeout is called.
If it fits better to you, you could even create a callback factory to pass a function call to setTimeout as #slebetman pointed out.
function callbackFactory (var) {
return function() {
sendInput(var);
}
};
setTimeout(callbackFactory('some_value'), 1000);

you can try
keyupTimer = setTimeout(function()
{
sendInput('test');
},1000);
so have an anonymous function as parameter for 'setTimeout'

it is also possible to use a string containing javascript code, as a first argument to setTimeout. however, it is strongly discouraged (see comments)
...
/* DON'T DO THIS: */
keyupTimer = setTimeout("sendInput(variable)", 1000)
...