Question

I’m learning javascript and noticed the following two syntaxes achieve the same end goal:

window.alert("chitty chitty bang bang!");
alert("chitty chitty bang bang!");

Also, why doesn’t this syntax work?

window.document.alert("chitty chitty bang bang!");

Answer 1

window is kind of the global scope of javascript. If you don’t specify a scope when calling a javascript function, this parent global scope is always assumed. As far as why window.document.alert doesn’t work is concerned, well, it’s because the alert function has been defined on the window global object and not on the window.document object which represents the DOM.