Identity Management (IdM) is a general term and encompasses technologies including password management (synchronisation and self reset), user provisioning and access management. Enables and maintains user access to network resources. This includes the creation of the user entity (functionality typically found in a human resource applications), authorization and permissions (SSO and password management functionality), and a single point of administration for de/provisioning accounts (as in provisioning)
Source: http://www.geneous-software.co.uk/glossary.htm