How do I add a file to the _layouts folder and have it recognized in the website?

I want to add a file Ratings.js to the ../TEMPLATE/LAYOUTS folder for my sharepoint solution, if I just paste开发者_JAVA百科 the file in there, how can I make it work with my sharepoint application, do I have to add it in the file to the site settings somewhere?

I cant reach it by going to http://site/_layouts/Ratings.js even though its in there.