A Zabbix item can be understood by its bare essentials—an identifier, data type, and associated host. These are the elements that are generally more useful for the rest of Zabbix's components. The identifier (that's usually the name and the associated item key) and the associated host are used to distinguish a single item among the thousands that can be defined in a monitoring environment. The data type is important so that Zabbix knows how to store the data, how to visualize it (text data won't be graphed, for example), and most importantly, what kind of functions can be applied to it in order to model triggers and the process further.
Tip
The item's name is a descriptive label that is meant to be easily read, while the item's key follows a specific syntax and defines exactly the metric that we want to measure.
Two other very important elements that are common to all the items are the history (and trends) retention period and item type. We already...