The equipment required for an AS/RS includes a Storage & Retrieval Machine, or SRM, that is used for rapid storage and retrieval of material. Common types of SRMs are mini load and unit load. An SRM moves loads on three axes: vertically and/or horizontally in the aisle and then laterally to place the load in a storage location. Automated Storage & Retrieval Systems vary in sophistication from relatively simple, manually-controlled order-picking machines operating in small storage structures to fully-automated, computer-controlled systems that are integrated into complex manufacturing and distribution processes. AS/RS is effective for staging in a lean inventory environment.