# Global footprint If you are developing a module, which might be running on a web page, which also runs other modules, 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;