title: Rails params explained?
body: <p>Could anyone explain <code>params</code> in Rails controller: where they come from, and what they are referencing?</p>
  
  <pre><code>  def create
      @vote = Vote.new(params[:vote])
      item = params[:vote][:item_id]
      uid = params[:vote][:user_id]
      @extant = Vote.find(:last, :conditions =&gt; ["item_id = ? AND user_id = ?", item, uid])
      last_vote_time = @extant.created_at unless @extant.blank?
      curr_time = Time.now
    end
  </code></pre>
  
  <p>I would like to be able to read this code line-by-line and understand what's going on.</p>