Google search engin

after searching in google.com or enter in google.com site in ie a .js file is created in “Temporary Internet Files” folder.
i want to know that what is this js file? and what is its work?
i attached one of that js file.

That’s the extern_js script that google loads, which is the library of code that they use.

can i see content of this file?
i want to know its work.

With IE for example, go to the developer tools and view the script file.
The file has formatting removed, so using something like http://jsbeautifier.org/ helps to make it easier to read.