Compare to ZPT:

http://www.zopemag.com/Issue003/Section_Articles/article_ZPTintro.html
<table>
  <tr tal:repeat="nr python:range(5)">
    <td tal:content="nr">show numbers 0 to 4</td>
  </tr>
</table>

<table>
<span tal:repeat="nr python:range(5)">
  <tr bgcolor="yellow" tal:condition="repeat/nr/odd">
    <td>odd</td>
  </tr>
  <tr bgcolor="white" tal:condition="repeat/nr/even">
    <td>even</td>
  </tr>
</span>
</table>

Or to Webware:

for i in range (5):
  self.write ('<tr><td>%d</td></tr>' % i)

Think of Nevow's lists as being like list comprehensions, vs. ZPT's explicit loops + python code in web page + condition syntax, or Webware's HTML tags in python code.