Setting the applicatiome Home Page
Generated a scaffold for the Post resource. This will represent a single blog posting.
Add validation to post.rb
Generated Comment model with Active Record association (association between Comment and Post models). e.g. $ rails generate model Comment commenter:string body:text post:references
Add association between Post and Comment
Created comments as a nested resource within posts
Created a controller for Comments
Wired up the Post show template, add a comment form to posts/show.html.erb
Hooking up Comments and Post. Added 'create' action in the CommentsController. It is used to keep track of the post to which the comment is attached. We use the create method on @post.commetns to create and save the comment. This will automatically link the comment so that it belongs to that particular post
Added where the comment is gonna be shown
Refactored partial: this will render the partial in
app/views/comments/_comment.html.erb once for each comment that is in
the @post.comments collection. As the render method iterates over the
@post.comments collection, it assigns each comment to a local variable
named the same as the partial
Refactored a partial form and render the partial template
Add delete link in the _comments.html.erb partial
Add destroy action to the controller
Modify model/post.rb, use dependent option of an association so when you delete a post, its associated comments will also be deleted.
Set authentication
Create a new model to hold the tags.  generate model tag name:string post:references
run rake db:migrate
Tell Rails(via the accepts_nested_attributes_for macro) that you intend to edit tags via posts. :allow_destroy option tells Rails to enable destroying tags throughout the nested attributes. The :reject_if option prevents saving new tags that do not have any attributes filled in. 
Added :tags_attributes to the attr_accessible list.