An unlimited number of groups can be applied to hosts and those hosts can belong to any template. It is good practice to have many groups associated with hosts so that it is easy to categorize them many different ways. For example, a host can belong to a group for the building name, a group of the host type, a group of host manufacture, a group of the network it resides on, and a group of any other information that may be shared among hosts.
Groups are also necessary for setting security permissions for user groups. Hosts must have groups or they cannot be assigned security permissions.
Below is an example of host “Ashly Amplifier” that belongs to five groups. You can see the groups the host is associated with by viewing the host itself, or you can see all groups and what hosts they are associated with by viewing the Host groups.