What does vfs.fs.size vfs mean?

[whntk]

What does vfs.fs.size vfs mean?
What does vm.memory.size vm mean?
Why use them to name it?
thank you.

[tcilmo]

What does vfs.fs.size vfs mean?
What does vm.memory.size vm mean?
Why use them to name it?
thank you.

The different item types\keys are outlined in the documentation for Z.

https://www.zabbix.com/documentation/3.4/manual/config/items/itemtypes/zabbix_agent