Can I add attributes to 'window' object in javascript?

Question

Can I add any random attribute to \'window\' object in javascript? Some thing like:

window.my_own_attr = \"my_value\"

Does it have any side

Answer 1

In IE if an element has an id, then that node is accessible on the window object as a property:

<div id="num"></div>

alert(num); //Element

num = 3; //throws exception

var num = 3; //ok