Template management consists of managing three Oracle Compute objects: the machine image (machineimage), the image list (imagelist), and the image list entry (imagelistentry).
A machine image object is a copy of a virtual hard disk with an installed operating system that is used to launch a virtual machine (VM). An image list object is an ordered sequence of machine image objects, one of which may be selected as the default version. This allows users to continue using the same imagelist while upgrades are made to the latest version (that is, users can boot a different machine image if the imagelist gets a new default version). The image list entries are used to add and remove machine images from an image list.