J1.5:How do I Remove Numbering on Section/Category Archive Page.
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This article is for Joomla! CMS Version(s) 
This page's content makes references relevant only for Joomla! CMS Version(s) and earlier →The use of "Section" has been deprecated from
and later Versions, please use: Categories.Remove Numbering on Section/Category Archive Page.
If you are referring to Category List Layout. You have to edit the file default_items.php located in the directory \components\com_content\views\category\tmpl to remove the number. In case if you have a file default_items.php located in the directory \components\your-template-name\com_content\category then you should edit that file.