# Global footprint

If you are developing an module, which might be running on a web page, which also runs other mudules, then you must beware the variable name overlapping.

Suppose we are developing a counter module:

var myCounter = {
number = 0,
plusPlus = function(){
this.number = this.number + 1;
},
isGreaterThanTen = function(){
return this.number > 10;
}
}


Note: this technique is often used with closures, to make the internal state immutable from the outside.

The module now takes only one variable name — myCounter. If any other module on the page makes use of such names like number or isGreaterThanTen then it's perfectly safe, because we will not override each others values;