If you have our 'Standard' package or above, you can host multiple websites by either utilising the "addon domains" function of cPanel, or by creating new and separate accounts within WHM.
For more information on "addon domains": http://docs.cpanel.net/twiki/bin/view/AllDocumentation/CpanelDocs/AddonDomains
For more information on WHM: http://www.thiswebhost.com/clients/knowledgebase.php?action=displayarticle&id=28