JS global variable pollution problem

JavaScript can arbitrarily define global variables that hold all application resources. But global variables can weaken program flexibility and increase the coupling between modules.
In multi-person collaboration, if you define too many global variables that can cause global variable conflicts, which is the global variable pollution problem, here are two solutions

I. Defining a global variable namespace

Creates only one global variable and defines the variable as the current application container, appending other global variables to the namespace

 var my={};  
  my.name={ 
  Big_name: "Zhangsan",  
  SMA Ll_name: "Lisi"  
  
  my.work={ 
  school_work: "study",  
  fam Ily_work: "We Are"  
   two.   wrap scripts with anonymous functions 
 
   

(function () {
    var exp={};
    var name= "AA";
    Exp.method=function () {
        return name;
    };
    Window.ex=exp;
})();
        Alert (Ex.method ())

JS global variable pollution problem