What Is ISO 27001
ISO 27001:2005 is actually applied variant of the BS 7799-2:2002 standard by the European Union Standards Organization.
ISO 27001:2005 is the successor of ISO 17799 (IT security management standard) and it is possible to certify an organization according to this standard.
Briefly ISO 27001 is a detailed description for how to create the IT Security Management System (ISMS).