how does scaffold works on ruby? how are the params defined? -

i using scaffold on ruby on rails, , great , all, makes simpler, dont understand 1 thing , books or web dont have clear solution.

for exmaple, use scaffold , create table user , can make /user/1 , see user id 1 , , if make /user/edit/1 edit user id number 1, on controller code this

  def show     @user = user.find(params[:id])      respond_to |format|       format.html # show.html.erb       format.json { render json: @user }     end   end 

according mvc ive worked, controller first in respond, so, in way should able indicate use show method, how? dont have else added on routes file. idea??

the default routes "http verb: get, path: /photos/:id, action: show, used for: display specific photo". see documentation.