Jquery not defined timing issues -

I am including jQuery in the head of a private site. I also included an external JS file which then uses jQuery.

  & lt; Script language = "javascript" src = "../ss / jquery-1.4.2.min.js" & gt; & Lt; / Script & gt; & Lt; Script language = "javascript" src = "../ss/ global.js" & gt; & Lt; / Script & gt;  

The global.js only contain the following:

  $ (".nav-item"). Hover (function {$ (this) AddClass ("selected");}, function () {$ (this) .removeClass ("selected");});  

When I tried it out, I was seeing that my error console was giving me "$ defining error" after carrying my external js file down to the page Everything works fine, apparently what is the right way to deal with what is the issue of a time?

Thanks in advance for any help

EDIT: It seems that when I saw an undefined error last night I would have to do something to get rid of it and I now have to do it View or Reproduce I tried to force the events into the document. Already, and it seems to solve my problem.

Did you bind document to global documents to prepare the document? In JS?