It’s not as easy to comment out big chunks of Rails erb (view) code. Here’s the one that seems to work fine for people:

<% if false %><!-- comment start -->
...
<% ... some code ... %>
some html
<% ... more code ... %>
<!-- comment end --><% end %>

If you simply try using HTML comments, the code will still execute.

Finally, if you want to simply comment out a single ERB statement, put # just after <%, like this:

<%# some ror code here %>
<%#= or some talking ror code here %>