So let's go a bit deeper into groups and see how to create them and link them with existing hosts. This duplicates the previous sentence. A host needs to be added to at least one group. Similar kind of hosts are grouped together even when the infrastructure is small.
You should have a running Zabbix installation and you should have the knowledge of the definitions. To be able to add groups, you also need frontend access through an admin or super admin account.
When we first create a group, we have an overview of the groups already available on our system. When you start with a clean installation, there are already some groups available; most importantly, the group Templates where all templates are grouped together and Zabbix servers where your Zabbix server is added and where you can put other Zabbix servers. Host groups in Zabbix are a logical way of putting servers in a group that have the same specifications, for example, all Linux servers, Windows servers, and so on.
Zabbix will never overwrite the standard templates when you upgrade but it can be good practice to create a template group just for your own or modified templ