JS since the call anonymous function concrete implementation

In js, a function is often defined as a temporary namespace in which variables are defined without polluting the global namespace (preventing local variables from colliding with global variables).

 
function mymodule(){ 
//Module code
} 
mymodule(); 

It can be abbreviated as:

 
(function(){ //The mymodule() function is overwritten as an anonymous function expression
//Module code
}( )<span style="color:#ff0000;">)</span>; //Close the function definition and call it immediately

Or:

 
(function(){ 

}<span style="color:#ff0000;">)</span>(); 

This method of defining anonymous functions and calling them immediately (from within) has become so common that it's starting to get a little confusing. The source code for jquery is written like this:

 
(function( window, undefined ) { 

//All the code for jquery
})( window );