1. CCK
http://drupal.org/project/cck
cck image
http://drupal.org/project/imagefield
http://www.drupal.org/project/imagecache
cck Media files
http://drupal.org/project/emfield
2. View
http://drupal.org/project/view
3. Menu
http://drupal.org/project/nice_menus
http://drupal.org/project/menu_trim
4. SEO
http://drupal.org/project/xmlsitemap
http://drupal.org/project/globalredirect
http://drupal.org/project/nodewords
*http://drupal.org/project/search404
Optional Modules
Event
http://drupal.org/project/event
Print
http://drupal.org/project/print
Captcha
http://drupal.org/project/captcha
Editor
WYSIWYM (What You See Is What You Mean) editor
http://drupal.org/project/wymeditor
WYMeditor is a lightweight XHTML/Javascript WYSIWYM (What You See Is What You Mean) editor.
http://drupal.org/project/bueditor
A plain textarea editor aiming to facilitate code writing.
Education Modules
http://drupal.org/project/quiz
Library Modules
http://drupal.org/project/marc
For Education
http://drupal.org/project/phpedu
Adds and maintains expiry dates for user accounts.
http://drupal.org/project/account_expiry
Confuzed about the similar function of modules? Read the "Comparisons of contributed modules" http://drupal.org/node/266179
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Note:
* optional.