A software is called multitenant if, running on a server or system, it can be used simultaneously by several clients (customers), each client having access only to his own data and objects. In addition, multitenant software distinguishes between customer-specific and cross-customer data and objects. The tenant represents the highest organizational and (data) architectural unit (e.g. thousands of websites of independent customers being hosted on one IP address by a webhost). Multitenant software is characterized mainly by its reduced memory footprint compared to other systems, since cross-customer data has to be saved only once per system (not once per tenant).