What is the difference between alert and window.alert?

Question

What is the difference between alert() and window.alert() functions? It seems to work the same.

Answer 1

Because window is the global object, you can call an alert either by it's shorthand: alert( 'Hello!' ); or by referencing the global object specifically: window.alert( 'Hello!' );

They are the same.

Answer 2

They are usually the same thing but, if in your scope, see example, the alert function got redefined then alert and window.alert will not be the same function.

(function () {     function alert(test) {         document.write(test);     }      alert("hello page");    window.alert("hello world"); })() 

Hope the example will shed more light on this subject than my explanation.

You can also shadow the function name with a variable and obtain an error when calling it.

(function () {     var alert;     alert("Why don't you work, silly function?"); })()