res.render(view [, locals] [, callback])
Renders a view and sends the rendered HTML string to the client. Optional parameters:
locals, an object whose properties define local variables for the view.
callback, a callback function. If provided, the method returns both the possible error and rendered string, but does not perform an automated response. When an error occurs, the method invokes next(err) internally.
The local variable cache enables view caching. Set it to true, to cache the view