Show raw HTML data and ruby variable.
concat this key word is the same as echo in PHP.
There is a array in the ruby controller that will be sent to a view.
@list = [2, 3, 5, 2, 3, 10, 6, 1]There three ways to do it!
<div>
    <% @list.each { |n|
        concat raw "<p>"
        concat n
        concat raw "</p>"
    } %>
</div><div>
    <% @list.each do |n| %>
        <p><%= n %></p>
    <% end %>
</div><div>
    <% @list.each do |n| %>
        <-- This tag is provided by ruby's view helper.  -->
        <%= tag_p n %>
    <% end %>
</div>Through this three we can make a good practice.